In this paper,we develop a novel hybrid automatic-repeat-request(ARQ)protocol for the quantum communication system using quantum stabilizer codes.The quantum information is encoded by stabilizer codes to against the c...In this paper,we develop a novel hybrid automatic-repeat-request(ARQ)protocol for the quantum communication system using quantum stabilizer codes.The quantum information is encoded by stabilizer codes to against the channel noise.The twophoton entangled state is prepared for codeword secure transmission.Hybrid ARQ protocol rules the recognition and retransmission of error codewords.In this protocol,the property of quantum entangled state ensures the security of information,the theory of hybrid ARQ system improves the reliability of transmission,the theory of quantum stabilizer codes corrects the flipping errors of codewords.Finally,we verify the security and throughput efficiency of this protocol.展开更多
<strong>Objective: </strong>The quantum dots are the useful materials in microelectronics and biomedical research. However its toxicity has to be considered. We studied the effect of cell inhibition with Z...<strong>Objective: </strong>The quantum dots are the useful materials in microelectronics and biomedical research. However its toxicity has to be considered. We studied the effect of cell inhibition with ZnS core quantum dots and CdTe quantum dots modified with Thioglycolic acid or Cysteine functional group (TGA-CdTe, TGA-CdTe/ZnS, Cys-CdTe, Cys-CdTe/ZnS) on Caco-2 cell proliferation. <strong>Methods</strong>: We studied the effect of cell inhibition with ZnS core QDs and CdTe QDs modified with functional group on Caco-2 cell proliferation by MTT assay at 0, 12.5, 25, 50, 100 μg/ml and 6, 24, 48 h. <strong>Result:</strong> Our results showed that all QDs have inhibited cell proliferation and reached maximum 79.21%. The inhibition rate of Cys-modified QDs increased with the increase of concentration and reached maximum 66.72%. The inhibition rate of TGA-modified QDs increased with the increase of time. The ratios of Cys-modified to TGA-modified were less than 1 at all concentrations and three exposure times (P ≤ 0.01). The average ratios of Cys-CdTe/ZnS to Cys-CdTe reached 1.11 only for 48 h (P ≤ 0.05). The ratios of TGA-CdTe/ZnS to TGA-CdTe were closed to 1 at all concentrations and exposure times. <strong>Conclusion:</strong> The regularity of QDs modified with functional group is that inhibition of TGA-modified higher than Cys-modified. Inhibition exhibited dose-dependent for Cys-modified while exhibited time-dependent for TGA-modified. The regularity of CdTe-QDs with ZnS or not is that the inhibition of Cys-CdTe/ZnS was higher than Cys-CdTe while TGA-CdTe/ZnS and TGA-CdTe were consistent.展开更多
The favored classical variables that are promoted to quantum operators are divided into three sets that feature constant positive curvatures, constant zero curvatures, as well as constant negative curvatures. This lis...The favored classical variables that are promoted to quantum operators are divided into three sets that feature constant positive curvatures, constant zero curvatures, as well as constant negative curvatures. This list covers the spin variables, the canonical variables, and the affine variables, and these three topics will be briefly reviewed. In this discussion, appropriate coherent states are introduced which are the principal items that are critical in the unification of relevant classical and quantum realms. This analysis can also serve to unify classical gravity and quantum gravity without any speculative aspects.展开更多
This paper represents a continuation of our Hypothesis of primary particles, which provides an opportunity for describing the origin of the Big Bang and other universes. In its hypothesis, we have shown that there was...This paper represents a continuation of our Hypothesis of primary particles, which provides an opportunity for describing the origin of the Big Bang and other universes. In its hypothesis, we have shown that there was a possibility of hypothetical primary particles moving in their own flat spacetime, in their basic, dynamic state and possessing speeds much higher than the speed of light, acquiring energy and momentum during deceleration in mutual collisions, which would tunnel into various universes. The cosmic microwave background is evidence that our universe expanded from a very hot, dense state, which is consistent with our hypothesis. The lower border speed to which a primary particle at the Big Bang came very close in a collision during its deceleration, simultaneously represents the upper border speed in our Universe—the speed of light in a vacuum. The speed of light, along with other fundamental physical constants, had shaped our Universe, in a manner in which we are still able to recognize the “physical gene” that preceded our existence. By virtue of comprehending our Universe, using the help of fundamental physical constants, we have determined that the mass attributed to the primary particle, in accordance with the Hypothesis of primary particles, would correspond to the Planck mass. Therefore, energy of the primary particle would be: <i>E<sub>p</sub></i> ≈ 1.22 × 10<sup>19</sup> GeV.展开更多
Any particular classical system and its quantum version are normally viewed as separate formulations that are strictly distinct. Our goal is to overcome the two separate languages and create a smooth and common proced...Any particular classical system and its quantum version are normally viewed as separate formulations that are strictly distinct. Our goal is to overcome the two separate languages and create a smooth and common procedure that provides a clear and continuous passage between the conventional distinction of either a strictly classical or a strictly quantized state. While path integration, among other procedures, provides an alternative route to connect classical and quantum expressions, it normally involves complicated, model-dependent, integrations. Our alternative procedures involve only model-independent procedures, and use more natural and straightforward integrations that are universal in kind. To introduce the basic procedures our presentation begins with familiar methods that are limited to basic, conventional, canonical quantum mechanical examples. In the final sections we illustrate how alternative quantization procedures, e.g., spin and affine quantizations, can also have smooth paths between classical and quantum stories, and with a few brief remarks, can also lead to similar stories for non-renormalizable covariant scalar fields as well as quantum gravity.展开更多
The similarity between classical and quantum physics is large enough to make an investigation of quantization methods a worthwhile endeavour. As history has shown, Dirac's canonical quantization method works reaso...The similarity between classical and quantum physics is large enough to make an investigation of quantization methods a worthwhile endeavour. As history has shown, Dirac's canonical quantization method works reasonably well in the case of conventional quantum mechanics over R<sup>n</sup> but it may fail in non-trivial phase spaces and also suffer from ordering problems. Affine quantization is an alternative method, similar to the canonical quantization, that may offer a positive result in situations for which canonical quantization fails. In this paper we revisit the affine quantization method on the half-line. We formulate and solve some simple models, the free particle and the harmonic oscillator.展开更多
In the solution of the Klein-Gordon equation for the shutter problem, we prove that, at internuclear distances, a relativistic beam of Pi-mesons has a probability density which oscillates in time in a similar way to t...In the solution of the Klein-Gordon equation for the shutter problem, we prove that, at internuclear distances, a relativistic beam of Pi-mesons has a probability density which oscillates in time in a similar way to the spatial dependence in optical Fresnel diffraction from a straight edge. However, for an extreme-relativistic beam, the Fresnel oscillations turn into quantum damped beat oscillations. We prove that quantum beat oscillations are the consequence, at extreme-relativistic velocities, of the interference between the initial incident wave function, and the Green’s function in the relativistic shutter problem. This is a pure quantum relativistic phenomenon.展开更多
We present a stochastic procedure to investigate the correlation spectra of quantum dot superluminescent diodes. The classical electric field of a diode is formed by a polychromatic superposition of many independent s...We present a stochastic procedure to investigate the correlation spectra of quantum dot superluminescent diodes. The classical electric field of a diode is formed by a polychromatic superposition of many independent stochastic oscillators. Assuming fields with individual carrier frequencies, Lorentzian linewidths and amplitudes we can form any relevant experimental spectrum using a least square fit. This is illustrated for Gaussian and Lorentzian spectra, Voigt profiles and box shapes. Eventually, the procedure is applied to an experimental spectrum of a quantum dot superluminescent diode which determines the first- and second-order temporal correlation functions of the emission. We find good agreement with the experimental data and a quantized treatment. Thus, a superposition of independent stochastic oscillators represents the first- and second-order correlation properties of broadband light emitted by quantum dot superluminescent diodes.展开更多
Quantum Mechanics’ entanglement and probabilistic behaviors are viewed in the light of Quantum Field Theory’s (QFT’s) advances made during the last century. In particular, Bohm’s version (B-EPR) of the Einstein, P...Quantum Mechanics’ entanglement and probabilistic behaviors are viewed in the light of Quantum Field Theory’s (QFT’s) advances made during the last century. In particular, Bohm’s version (B-EPR) of the Einstein, Podolsky, Rosen (EPR) experiment is now viewed with the aid of QFT’s modern description of electrons. In QFT, free electrons possess a bare core surrounded by a “dressing”. The dressing consists of one or more virtual particles/fields pulled from the vacuum during the bound electron’s parturition. In QFT, a bound electron’s freedom is aided by eliminating its energy losses from bremsstrahlung. The paper develops a “Shimony” numerical model using QFT’s free electron structure with the aid of a “random vector paradigm” (RVP). The RVP simply expresses QFT’s free electron as a bare core surrounded by an EM dressing. Using this RVP, we imbue newly freed electrons with a vector-like EM spin property of 1/2. From this, the Shimony Monte Carlo computer analysis provides a detailed comparison of the B-EPR experiment as described by Bell. The entanglement property can serve to provide a way to transport shared encoded information. Overall, the electron dressing can convey random elements that may provide QM with its entanglement and probabilistic behaviors.展开更多
Quantum chemistry methods were performed in order to characterize the chemical reactivity on series of imidazo[1,2-a]pyridinyl-chalcone (IPC). In particular, the B3LYP/6-311G(d) theory level has been used to determine...Quantum chemistry methods were performed in order to characterize the chemical reactivity on series of imidazo[1,2-a]pyridinyl-chalcone (IPC). In particular, the B3LYP/6-311G(d) theory level has been used to determine parameters which characterize the global and local reactivity on five molecules of the series. These compounds differ from one to another with the aryl groups. There are: 1-(2-methylimidazo[1,2-a]pyridin-3-yl)-3-phenylprop-2-en-1-one, 3-(4-fluorophenyl)-1-(2-methylimidazo [1,2-a]pyridin-3-yl)prop-2-en-1-one, 3-[4-(dimethylamino)phenyl]-1-(2-methylimidazo [1,2-a]pyridin- 3-yl)prop-2-en-1-one, 3-(2,4-dichlorophenyl)-1-(2-methylimidazo [1,2-a]pyridin-3-yl)prop-2-en-1-one, 3-(2,4-dichlorophenyl)-1-(2-methylimidazo [1,2-a]pyridin-3-yl)prop-2-en-1-one. All results lead to finding out that local nucleophilicity and electrophilicity of compounds are not substituent-dependant contrarily to their global nucleophilicity which prove to be more sensitive to the electron-donating character of the substituents. 3-[4-(Dimethylamino) phenyl]-1-(2-methylimidazo[1,2-a]pyridin-3-yl)prop-2-en-1-one was identified as the unique nucleophile compound by global reactivity. Respectively, the carbon atoms C5 and C14 are the prediction sites of electrophilic and nucleophilic attacks in the molecular skeleton of both molecules. Identification of interactions centres on IPC series is of great importance for organic synthesis and medicinal chemistry where the molecular hybridization strategy is very often used to improve biological activities of interesting therapeutic systems.展开更多
Copper corrosion inhibition by Emilia sonchifolia (ES) leaf extract has been studied in 2 M hydrochloric acid solution using electrochemical measurement, energy dispersive X-ray emission spectroscopy and surface exami...Copper corrosion inhibition by Emilia sonchifolia (ES) leaf extract has been studied in 2 M hydrochloric acid solution using electrochemical measurement, energy dispersive X-ray emission spectroscopy and surface examination techniques. Computational simulations were adopted to describe probable reactiveness of individual ES leaf constituents and mechanism of interaction with copper crystal. Results obtained from potentiodynamic polarization revealed a shift in corrosion potentials of copper (CU131729) to more positive potentials in the presence of ES leaf extract with increased effect as inhibitor concentration increased and also a decrease in both current densities suggesting a mixed type inhibitor characteristics with pronounced anodic protection. Surface elemental characterization revealed presence of the inhibitor species in the corrosion products formed on corroded CU131729 surface confirming the formation of complex chelating ligands through interactions with the metal surface. Quantum chemical calculations and molecular dynamics simulations were employed to theoretically analyse the interactions of individual ES leaf constituent with copper surface at the molecular level and obtained results revealed strong and spontaneous adsorption with high binding energies which affirms observed quality inhibition action. Quantum chemical descriptors such as energy of HOMO and LUMO, energy gap, number of transferred electrons, global hardness and softness, electrophilicity, and interaction energy were computed and discussed.展开更多
The efficacy and mode of action of five chalcone-based imidazole derivatives as corrosion inhibitors of aluminium metal in gas-phase and acidic medium have been investigated herein via quantum chemical calculations. D...The efficacy and mode of action of five chalcone-based imidazole derivatives as corrosion inhibitors of aluminium metal in gas-phase and acidic medium have been investigated herein via quantum chemical calculations. Dispersion-corrected DFT (DFT-D3) and time-dependent DFT (TD-DFT) calculations were performed at PBE0/def2-TZVP//PBEh-3c and CAM-B3LYP/def2- TZVP levels of theory, respectively. Conceptual DFT, the quantum theory of atoms-in-molecules (QTAIM) and local energy decomposition (LED) analyses have been performed. The LED analysis was performed at the coupled-cluster singles and doubles with perturbative triples (CCSD(T))/def2-SVP level of theory. Frontier molecular orbital energy gaps calculated using the TD-DFT method are found to lie in the range 3.574 - 4.444 eV, indicative of good adsorption and corrosion inhibition efficacies of the investigated molecules. The interactions between aluminium and the inhibitor molecules studied are found to be energetically favorable, owing to negative computed interaction energy values. Furthermore, QTAIM analysis revealed metal-carbon, metal-oxygen and metal-nitrogen interactions in the inhibitor-aluminium complexes, which are predominantly electrostatic in character, according to LED analysis results. Calculated proton affinities (PAs) have revealed the anticorrosion potentials of the investigated inhibitors in acidic medium, with a noticeable dependency on temperature within the range 273.15 - 343.15 K.展开更多
The energy level separation between the edge states in topological insulator quantum dots lies in the terahertz(THz) range.Quantum confinement ensures the nonuniformity of the energy level separation near the Dirac po...The energy level separation between the edge states in topological insulator quantum dots lies in the terahertz(THz) range.Quantum confinement ensures the nonuniformity of the energy level separation near the Dirac point. Based on these features, we propose that a topological insulator quantum dot array can be operated as an electrically pumped continuous-wave THz laser. The proposed device can operate at room temperature, with power exceeding 10 mW and quantum efficiency reaching ~50%. This study may promote the usage of topological insulator quantum dots as an important source of THz radiation.展开更多
In this paper,by introducing the Lorentz-invariance-violation(LIV)class of dispersion relations(DR)suppressed by the second power(E/Eqg)2,we investigated the effect of the LIV on the Hawking radiation of a charged Dir...In this paper,by introducing the Lorentz-invariance-violation(LIV)class of dispersion relations(DR)suppressed by the second power(E/Eqg)2,we investigated the effect of the LIV on the Hawking radiation of a charged Dirac particle based on tunneling from a Reissner-Nordstrom(RN)black hole.It was determined that the LIV speeds up black hole evaporation.As a result,the induced Hawking temperature was very sensitive to changes in the energy of the radiation particle.However,at the same energy level,it was insensitive to changes in the charge of the radiation particle.This is phenomenological evidence in support of the LIV-DR as a candidate for describing the effect of quantum gravity.Moreover,when the effect of the LIV was in eluded,we discovered that the statistical correlations with the Planck-scale corrections between successive emissions could leak out information via radiation.We also determined that black hole radiation via tunneling is an entropy conservation process,and no information loss occurred during radiation,where the interpretatio n of the entropy of a biack hole is addressed.Fin ally,we concluded that black hole evaporation is still a unitary process in the context of quantum gravity.展开更多
The generation and manipulation of strong entanglement and Einstein-Podolsky-Rosen(EPR)steering in macroscopic systems are outstanding challenges in modern physics.Especially,the observation of asymmetric EPR steering...The generation and manipulation of strong entanglement and Einstein-Podolsky-Rosen(EPR)steering in macroscopic systems are outstanding challenges in modern physics.Especially,the observation of asymmetric EPR steering is important for both its fundamental role in interpreting the nature of quantum mechanics and its application as resource for the tasks where the levels of trust at different parties are highly asymmetric.Here,we study the entanglement and EPR steering between two macroscopic magnons in a hybrid ferrimagnet—light system.In the absence of light,the two types of magnons on the two sublattices can be entangled,but no quantum steering occurs when they are damped with the same rates.In the presence of the cavity field,the entanglement can be significantly enhanced,and strong two-way asymmetric quantum steering appears between two magnons with equal dissipation.This is very different from the conventional protocols to produce asymmetric steering by imposing additional unbalanced losses or noises on the two parties at the cost of reducing steerability.The essential physics is well understood by the unbalanced population of acoustic and optical magnons under the cooling effect of cavity photons.Our finding may provide a novel platform to manipulate the quantum steering and the detection of bi-party steering provides a knob to probe the magnetic damping on each sublattice of a magnet.展开更多
Remote tracking the variation of air quality in an effective way will be highly helpful to decrease the health risk of human short-and long-term exposures to air pollution.However,high power consumption and poor sensi...Remote tracking the variation of air quality in an effective way will be highly helpful to decrease the health risk of human short-and long-term exposures to air pollution.However,high power consumption and poor sensing performance remain the concerned issues,thereby limiting the scale-up in deploying air quality tracking networks.Herein,we report a standalone-like smart device that can remotely track the variation of air pollutants in a power-saving way.Brevity,the created smart device demonstrated satisfactory selectivity(against six kinds of representative exhaust gases or air pollutants),desirable response magnitude(164–100 ppm),and acceptable response/recovery rate(52.0/50.5 s),as well as linear response relationship to NO2.After aging for 2 weeks,the created device exhibited relatively stable sensing performance more than 3 months.Moreover,a photoluminescence-enhanced light fidelity(Li-Fi)telecommunication technique is proposed and the Li-Fi communication distance is significantly extended.Conclusively,our reported standalone-like smart device would sever as a powerful sensing platform to construct high-performance and low-power consumption air quality wireless sensor networks and to prevent air pollutant-induced diseases via a more effective and low-cost approach.展开更多
Magnons,the collective excitation of magnetically ordered materials,have attracted considerable interest for their low energy consumption,long coherence time and useful working frequency from gigahertz to terahertz.Be...Magnons,the collective excitation of magnetically ordered materials,have attracted considerable interest for their low energy consumption,long coherence time and useful working frequency from gigahertz to terahertz.Besides,magnons can coherently interact with phonons,microwave and optical photons,as well as superconducting qubits,as schematically depicted in Figure 1,providing a novel platform to achieve hybrid quantum systems[1].Hybridizing distinct quantum systems with multitasking capabilities is critical in quantum information processing,because a single quantum system cannot keep pace with the fast development of quantum information and satisfy the requirement of building perfect quantum information networks[2].The emergying field cavity spintronics has inspired many interesting physics like nonreciprocal microwave propagation and energy level attraction,together with quite a few applications such as magnon sensors and magnon-photon transducers.展开更多
Realization of robust quantum computing is a tremendous task.On one hand,one must reduce errors as many as possible using various means[1-3];on the other hand,one may make large error rates tolerable via fault-toleran...Realization of robust quantum computing is a tremendous task.On one hand,one must reduce errors as many as possible using various means[1-3];on the other hand,one may make large error rates tolerable via fault-tolerant implementation.In achieving tolerant against noises,the cost to pay is the increased number of gates used.Therefore,an efficient implementation of fault-tolerant gates is crucial.As already evidenced,Clifford gates with a T gate can form a universal set of fault-tolerant gates.展开更多
Dirac’s rule in which only special phase space variables should be promoted to operators in canonical quantization is applied to loop quantum gravity. For this theory, Dirac’s rule is violated, and as a result loop ...Dirac’s rule in which only special phase space variables should be promoted to operators in canonical quantization is applied to loop quantum gravity. For this theory, Dirac’s rule is violated, and as a result loop quantum gravity fails the test to be a valid quantization. Indications are included on how to create and deal with valid versions of quantum gravity.展开更多
基金The work is supported by was supported by the Shandong Province Higher Educational Science and Technology Program(Grant No.J18KZ012)the National Natural Science Foundation of China(Grant No.11975132,61772295)the Shandong Provincial Natural Science Foundation,China(Grant No.ZR2019YQ01).
文摘In this paper,we develop a novel hybrid automatic-repeat-request(ARQ)protocol for the quantum communication system using quantum stabilizer codes.The quantum information is encoded by stabilizer codes to against the channel noise.The twophoton entangled state is prepared for codeword secure transmission.Hybrid ARQ protocol rules the recognition and retransmission of error codewords.In this protocol,the property of quantum entangled state ensures the security of information,the theory of hybrid ARQ system improves the reliability of transmission,the theory of quantum stabilizer codes corrects the flipping errors of codewords.Finally,we verify the security and throughput efficiency of this protocol.
文摘<strong>Objective: </strong>The quantum dots are the useful materials in microelectronics and biomedical research. However its toxicity has to be considered. We studied the effect of cell inhibition with ZnS core quantum dots and CdTe quantum dots modified with Thioglycolic acid or Cysteine functional group (TGA-CdTe, TGA-CdTe/ZnS, Cys-CdTe, Cys-CdTe/ZnS) on Caco-2 cell proliferation. <strong>Methods</strong>: We studied the effect of cell inhibition with ZnS core QDs and CdTe QDs modified with functional group on Caco-2 cell proliferation by MTT assay at 0, 12.5, 25, 50, 100 μg/ml and 6, 24, 48 h. <strong>Result:</strong> Our results showed that all QDs have inhibited cell proliferation and reached maximum 79.21%. The inhibition rate of Cys-modified QDs increased with the increase of concentration and reached maximum 66.72%. The inhibition rate of TGA-modified QDs increased with the increase of time. The ratios of Cys-modified to TGA-modified were less than 1 at all concentrations and three exposure times (P ≤ 0.01). The average ratios of Cys-CdTe/ZnS to Cys-CdTe reached 1.11 only for 48 h (P ≤ 0.05). The ratios of TGA-CdTe/ZnS to TGA-CdTe were closed to 1 at all concentrations and exposure times. <strong>Conclusion:</strong> The regularity of QDs modified with functional group is that inhibition of TGA-modified higher than Cys-modified. Inhibition exhibited dose-dependent for Cys-modified while exhibited time-dependent for TGA-modified. The regularity of CdTe-QDs with ZnS or not is that the inhibition of Cys-CdTe/ZnS was higher than Cys-CdTe while TGA-CdTe/ZnS and TGA-CdTe were consistent.
文摘The favored classical variables that are promoted to quantum operators are divided into three sets that feature constant positive curvatures, constant zero curvatures, as well as constant negative curvatures. This list covers the spin variables, the canonical variables, and the affine variables, and these three topics will be briefly reviewed. In this discussion, appropriate coherent states are introduced which are the principal items that are critical in the unification of relevant classical and quantum realms. This analysis can also serve to unify classical gravity and quantum gravity without any speculative aspects.
文摘This paper represents a continuation of our Hypothesis of primary particles, which provides an opportunity for describing the origin of the Big Bang and other universes. In its hypothesis, we have shown that there was a possibility of hypothetical primary particles moving in their own flat spacetime, in their basic, dynamic state and possessing speeds much higher than the speed of light, acquiring energy and momentum during deceleration in mutual collisions, which would tunnel into various universes. The cosmic microwave background is evidence that our universe expanded from a very hot, dense state, which is consistent with our hypothesis. The lower border speed to which a primary particle at the Big Bang came very close in a collision during its deceleration, simultaneously represents the upper border speed in our Universe—the speed of light in a vacuum. The speed of light, along with other fundamental physical constants, had shaped our Universe, in a manner in which we are still able to recognize the “physical gene” that preceded our existence. By virtue of comprehending our Universe, using the help of fundamental physical constants, we have determined that the mass attributed to the primary particle, in accordance with the Hypothesis of primary particles, would correspond to the Planck mass. Therefore, energy of the primary particle would be: <i>E<sub>p</sub></i> ≈ 1.22 × 10<sup>19</sup> GeV.
文摘Any particular classical system and its quantum version are normally viewed as separate formulations that are strictly distinct. Our goal is to overcome the two separate languages and create a smooth and common procedure that provides a clear and continuous passage between the conventional distinction of either a strictly classical or a strictly quantized state. While path integration, among other procedures, provides an alternative route to connect classical and quantum expressions, it normally involves complicated, model-dependent, integrations. Our alternative procedures involve only model-independent procedures, and use more natural and straightforward integrations that are universal in kind. To introduce the basic procedures our presentation begins with familiar methods that are limited to basic, conventional, canonical quantum mechanical examples. In the final sections we illustrate how alternative quantization procedures, e.g., spin and affine quantizations, can also have smooth paths between classical and quantum stories, and with a few brief remarks, can also lead to similar stories for non-renormalizable covariant scalar fields as well as quantum gravity.
文摘The similarity between classical and quantum physics is large enough to make an investigation of quantization methods a worthwhile endeavour. As history has shown, Dirac's canonical quantization method works reasonably well in the case of conventional quantum mechanics over R<sup>n</sup> but it may fail in non-trivial phase spaces and also suffer from ordering problems. Affine quantization is an alternative method, similar to the canonical quantization, that may offer a positive result in situations for which canonical quantization fails. In this paper we revisit the affine quantization method on the half-line. We formulate and solve some simple models, the free particle and the harmonic oscillator.
文摘In the solution of the Klein-Gordon equation for the shutter problem, we prove that, at internuclear distances, a relativistic beam of Pi-mesons has a probability density which oscillates in time in a similar way to the spatial dependence in optical Fresnel diffraction from a straight edge. However, for an extreme-relativistic beam, the Fresnel oscillations turn into quantum damped beat oscillations. We prove that quantum beat oscillations are the consequence, at extreme-relativistic velocities, of the interference between the initial incident wave function, and the Green’s function in the relativistic shutter problem. This is a pure quantum relativistic phenomenon.
文摘We present a stochastic procedure to investigate the correlation spectra of quantum dot superluminescent diodes. The classical electric field of a diode is formed by a polychromatic superposition of many independent stochastic oscillators. Assuming fields with individual carrier frequencies, Lorentzian linewidths and amplitudes we can form any relevant experimental spectrum using a least square fit. This is illustrated for Gaussian and Lorentzian spectra, Voigt profiles and box shapes. Eventually, the procedure is applied to an experimental spectrum of a quantum dot superluminescent diode which determines the first- and second-order temporal correlation functions of the emission. We find good agreement with the experimental data and a quantized treatment. Thus, a superposition of independent stochastic oscillators represents the first- and second-order correlation properties of broadband light emitted by quantum dot superluminescent diodes.
文摘Quantum Mechanics’ entanglement and probabilistic behaviors are viewed in the light of Quantum Field Theory’s (QFT’s) advances made during the last century. In particular, Bohm’s version (B-EPR) of the Einstein, Podolsky, Rosen (EPR) experiment is now viewed with the aid of QFT’s modern description of electrons. In QFT, free electrons possess a bare core surrounded by a “dressing”. The dressing consists of one or more virtual particles/fields pulled from the vacuum during the bound electron’s parturition. In QFT, a bound electron’s freedom is aided by eliminating its energy losses from bremsstrahlung. The paper develops a “Shimony” numerical model using QFT’s free electron structure with the aid of a “random vector paradigm” (RVP). The RVP simply expresses QFT’s free electron as a bare core surrounded by an EM dressing. Using this RVP, we imbue newly freed electrons with a vector-like EM spin property of 1/2. From this, the Shimony Monte Carlo computer analysis provides a detailed comparison of the B-EPR experiment as described by Bell. The entanglement property can serve to provide a way to transport shared encoded information. Overall, the electron dressing can convey random elements that may provide QM with its entanglement and probabilistic behaviors.
文摘Quantum chemistry methods were performed in order to characterize the chemical reactivity on series of imidazo[1,2-a]pyridinyl-chalcone (IPC). In particular, the B3LYP/6-311G(d) theory level has been used to determine parameters which characterize the global and local reactivity on five molecules of the series. These compounds differ from one to another with the aryl groups. There are: 1-(2-methylimidazo[1,2-a]pyridin-3-yl)-3-phenylprop-2-en-1-one, 3-(4-fluorophenyl)-1-(2-methylimidazo [1,2-a]pyridin-3-yl)prop-2-en-1-one, 3-[4-(dimethylamino)phenyl]-1-(2-methylimidazo [1,2-a]pyridin- 3-yl)prop-2-en-1-one, 3-(2,4-dichlorophenyl)-1-(2-methylimidazo [1,2-a]pyridin-3-yl)prop-2-en-1-one, 3-(2,4-dichlorophenyl)-1-(2-methylimidazo [1,2-a]pyridin-3-yl)prop-2-en-1-one. All results lead to finding out that local nucleophilicity and electrophilicity of compounds are not substituent-dependant contrarily to their global nucleophilicity which prove to be more sensitive to the electron-donating character of the substituents. 3-[4-(Dimethylamino) phenyl]-1-(2-methylimidazo[1,2-a]pyridin-3-yl)prop-2-en-1-one was identified as the unique nucleophile compound by global reactivity. Respectively, the carbon atoms C5 and C14 are the prediction sites of electrophilic and nucleophilic attacks in the molecular skeleton of both molecules. Identification of interactions centres on IPC series is of great importance for organic synthesis and medicinal chemistry where the molecular hybridization strategy is very often used to improve biological activities of interesting therapeutic systems.
文摘Copper corrosion inhibition by Emilia sonchifolia (ES) leaf extract has been studied in 2 M hydrochloric acid solution using electrochemical measurement, energy dispersive X-ray emission spectroscopy and surface examination techniques. Computational simulations were adopted to describe probable reactiveness of individual ES leaf constituents and mechanism of interaction with copper crystal. Results obtained from potentiodynamic polarization revealed a shift in corrosion potentials of copper (CU131729) to more positive potentials in the presence of ES leaf extract with increased effect as inhibitor concentration increased and also a decrease in both current densities suggesting a mixed type inhibitor characteristics with pronounced anodic protection. Surface elemental characterization revealed presence of the inhibitor species in the corrosion products formed on corroded CU131729 surface confirming the formation of complex chelating ligands through interactions with the metal surface. Quantum chemical calculations and molecular dynamics simulations were employed to theoretically analyse the interactions of individual ES leaf constituent with copper surface at the molecular level and obtained results revealed strong and spontaneous adsorption with high binding energies which affirms observed quality inhibition action. Quantum chemical descriptors such as energy of HOMO and LUMO, energy gap, number of transferred electrons, global hardness and softness, electrophilicity, and interaction energy were computed and discussed.
文摘The efficacy and mode of action of five chalcone-based imidazole derivatives as corrosion inhibitors of aluminium metal in gas-phase and acidic medium have been investigated herein via quantum chemical calculations. Dispersion-corrected DFT (DFT-D3) and time-dependent DFT (TD-DFT) calculations were performed at PBE0/def2-TZVP//PBEh-3c and CAM-B3LYP/def2- TZVP levels of theory, respectively. Conceptual DFT, the quantum theory of atoms-in-molecules (QTAIM) and local energy decomposition (LED) analyses have been performed. The LED analysis was performed at the coupled-cluster singles and doubles with perturbative triples (CCSD(T))/def2-SVP level of theory. Frontier molecular orbital energy gaps calculated using the TD-DFT method are found to lie in the range 3.574 - 4.444 eV, indicative of good adsorption and corrosion inhibition efficacies of the investigated molecules. The interactions between aluminium and the inhibitor molecules studied are found to be energetically favorable, owing to negative computed interaction energy values. Furthermore, QTAIM analysis revealed metal-carbon, metal-oxygen and metal-nitrogen interactions in the inhibitor-aluminium complexes, which are predominantly electrostatic in character, according to LED analysis results. Calculated proton affinities (PAs) have revealed the anticorrosion potentials of the investigated inhibitors in acidic medium, with a noticeable dependency on temperature within the range 273.15 - 343.15 K.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB28000000)the National Natural Science Foundation of China(Grant Nos.61674145,11974340,11434010,11574303,and 11774021)+2 种基金the Ministry of Science and Technology of the People’s Republic of China(Grant Nos.2018YFA0306101,and 2017YFA0303400)the Chinese Academy of Sciences(Grant No.QYZDJSSW-SYS001,and XXH13506-202)the NSFC program for the“Scientific Research Center”(Grant No.U1930402)。
文摘The energy level separation between the edge states in topological insulator quantum dots lies in the terahertz(THz) range.Quantum confinement ensures the nonuniformity of the energy level separation near the Dirac point. Based on these features, we propose that a topological insulator quantum dot array can be operated as an electrically pumped continuous-wave THz laser. The proposed device can operate at room temperature, with power exceeding 10 mW and quantum efficiency reaching ~50%. This study may promote the usage of topological insulator quantum dots as an important source of THz radiation.
基金Supported by the National Natural Science Foundation of China(11903025)by the starting fund of China West Normal University(18Q062)+1 种基金by the Natural Science Foundation of Sichuan Education Department(17ZA0294)by the Research Project of Si Chuan MinZu College(XYZB18003ZA)。
文摘In this paper,by introducing the Lorentz-invariance-violation(LIV)class of dispersion relations(DR)suppressed by the second power(E/Eqg)2,we investigated the effect of the LIV on the Hawking radiation of a charged Dirac particle based on tunneling from a Reissner-Nordstrom(RN)black hole.It was determined that the LIV speeds up black hole evaporation.As a result,the induced Hawking temperature was very sensitive to changes in the energy of the radiation particle.However,at the same energy level,it was insensitive to changes in the charge of the radiation particle.This is phenomenological evidence in support of the LIV-DR as a candidate for describing the effect of quantum gravity.Moreover,when the effect of the LIV was in eluded,we discovered that the statistical correlations with the Planck-scale corrections between successive emissions could leak out information via radiation.We also determined that black hole radiation via tunneling is an entropy conservation process,and no information loss occurred during radiation,where the interpretatio n of the entropy of a biack hole is addressed.Fin ally,we concluded that black hole evaporation is still a unitary process in the context of quantum gravity.
基金supported by the National Natural Science Foundation of China(Grant Nos.11975026,61475007,and 61704071)the National Key Research and Development Program of China(Grant Nos.2018YFB1107200,and 2016YFA0301302)+1 种基金the Key Research and Development Program of Guangzhou Province(Grant No.2018B030329001)the Beijing Natural Science Foundation(Grant No.Z190005)。
文摘The generation and manipulation of strong entanglement and Einstein-Podolsky-Rosen(EPR)steering in macroscopic systems are outstanding challenges in modern physics.Especially,the observation of asymmetric EPR steering is important for both its fundamental role in interpreting the nature of quantum mechanics and its application as resource for the tasks where the levels of trust at different parties are highly asymmetric.Here,we study the entanglement and EPR steering between two macroscopic magnons in a hybrid ferrimagnet—light system.In the absence of light,the two types of magnons on the two sublattices can be entangled,but no quantum steering occurs when they are damped with the same rates.In the presence of the cavity field,the entanglement can be significantly enhanced,and strong two-way asymmetric quantum steering appears between two magnons with equal dissipation.This is very different from the conventional protocols to produce asymmetric steering by imposing additional unbalanced losses or noises on the two parties at the cost of reducing steerability.The essential physics is well understood by the unbalanced population of acoustic and optical magnons under the cooling effect of cavity photons.Our finding may provide a novel platform to manipulate the quantum steering and the detection of bi-party steering provides a knob to probe the magnetic damping on each sublattice of a magnet.
基金the financial support for this research from the National Key Research and Development Program of China(Grant No.2017YFA0205301)National Natural Science Foundation of China(Grant No.61771267,61774106)+6 种基金Oceanic Interdisciplinary Program of Shanghai Jiao Tong University(Grant No.BX2020208)Shanghai Natural Science Foundation(Grant No.86973)Natural Science Foundation of Ningbo City(Grant No.2017A610229)National Postdoctoral Program for Innovative Talents(Grant No.BX20190205)Special fund for science and technology innovation of Shanghai Jiao Tong University(Grant No.YG2017MS70)Shanghai Municipal Bureau of Economy and Information Technology(Grant No.XC-ZXSJ-02-2016-05)China Postdoctoral Science Foundation.
文摘Remote tracking the variation of air quality in an effective way will be highly helpful to decrease the health risk of human short-and long-term exposures to air pollution.However,high power consumption and poor sensing performance remain the concerned issues,thereby limiting the scale-up in deploying air quality tracking networks.Herein,we report a standalone-like smart device that can remotely track the variation of air pollutants in a power-saving way.Brevity,the created smart device demonstrated satisfactory selectivity(against six kinds of representative exhaust gases or air pollutants),desirable response magnitude(164–100 ppm),and acceptable response/recovery rate(52.0/50.5 s),as well as linear response relationship to NO2.After aging for 2 weeks,the created device exhibited relatively stable sensing performance more than 3 months.Moreover,a photoluminescence-enhanced light fidelity(Li-Fi)telecommunication technique is proposed and the Li-Fi communication distance is significantly extended.Conclusively,our reported standalone-like smart device would sever as a powerful sensing platform to construct high-performance and low-power consumption air quality wireless sensor networks and to prevent air pollutant-induced diseases via a more effective and low-cost approach.
文摘Magnons,the collective excitation of magnetically ordered materials,have attracted considerable interest for their low energy consumption,long coherence time and useful working frequency from gigahertz to terahertz.Besides,magnons can coherently interact with phonons,microwave and optical photons,as well as superconducting qubits,as schematically depicted in Figure 1,providing a novel platform to achieve hybrid quantum systems[1].Hybridizing distinct quantum systems with multitasking capabilities is critical in quantum information processing,because a single quantum system cannot keep pace with the fast development of quantum information and satisfy the requirement of building perfect quantum information networks[2].The emergying field cavity spintronics has inspired many interesting physics like nonreciprocal microwave propagation and energy level attraction,together with quite a few applications such as magnon sensors and magnon-photon transducers.
文摘Realization of robust quantum computing is a tremendous task.On one hand,one must reduce errors as many as possible using various means[1-3];on the other hand,one may make large error rates tolerable via fault-tolerant implementation.In achieving tolerant against noises,the cost to pay is the increased number of gates used.Therefore,an efficient implementation of fault-tolerant gates is crucial.As already evidenced,Clifford gates with a T gate can form a universal set of fault-tolerant gates.
基金supported by the National Key R&D Program of China(2019YFA0308700,2017YFA0303700)the National Natural Science Foundation of China(61734005,11761141014,and 11690033)+2 种基金the Science and Technology Commission of Shanghai Municipality(15QA1402200,16JC1400405,and 17JC1400403)the Shanghai Municipal Education Commission(16SG09 and 2017-01-07-00-02-E00049)additional support from a Shanghai Talent Program.
文摘Dirac’s rule in which only special phase space variables should be promoted to operators in canonical quantization is applied to loop quantum gravity. For this theory, Dirac’s rule is violated, and as a result loop quantum gravity fails the test to be a valid quantization. Indications are included on how to create and deal with valid versions of quantum gravity.