Balancing the adsorption of OH⁻and 5-hydroxymethylfurfural(HMF)is crucial in optimizing the competing HMF oxidation reaction and oxygen evolution reaction,especially given the polymerization tendency of HMF in alkalin...Balancing the adsorption of OH⁻and 5-hydroxymethylfurfural(HMF)is crucial in optimizing the competing HMF oxidation reaction and oxygen evolution reaction,especially given the polymerization tendency of HMF in alkaline solutions.Herein,we present an innovative approach for rapidly synthesizing a NiFe bimetallic metalorganic framework(MOF)induced by electron-withdrawing carbon quantum dot(EW-CQD)via electron beam irradiation within 2 min.EW-CQD serve as structural regulators,expanding the NiFe-MOF interlayer spacing,increasing reactive site availability,and more effectively balancing the adsorption of OH6(-) and HMF,thereby significantly boosting the oxidation activity of HMF.The resulting EW-CQD-MOF exhibits a low potential of 1.36 V vs.RHE at 10 mA cm^(-2)and maintains excellent durability over 120 h.Comprehensive in situ characterization elucidates the HMF oxidation reaction pathway,showing high selectivity towards 2,5-furandicarboxylic acid(FDCA)under ambient conditions,with an impressive HMF conversion rate of 94%and FDCA selectivity of 96%within 6 h.These findings underscore the critical role of structural optimization and adsorption balance in catalytic performance enhancement and offer valuable insights for designing high-efficiency catalysts,advancing sustainable catalytic processes.展开更多
The growing environmental concerns regarding rare earth elements in fluorescent powders,along with high production costs,have increased the demand for sustainable alternatives.We propose a promising solution using lum...The growing environmental concerns regarding rare earth elements in fluorescent powders,along with high production costs,have increased the demand for sustainable alternatives.We propose a promising solution using luminescent metal-organic frameworks(LMOFs)with large surface areas and tunable pore structures,combined with organic carbon quantum dots(CQDs).This study develops a novel white lightemitting diode(WLED)fluorescent powder by incorporating yellow-fluorescent quantum dots(CQDs-Y)into blue-emitting LMOF(ZJU-28),forming the composite material CQDs-Y-n@ZJU-28.The composite exhibits excellent thermal and chemical stability,long-term storage performance,and emits warm white light(CIE:0.3277,0.3281)when subjected to excitation at 365 nm,along with an external quantum efficiency(EQE)of 8.85%.Furthermore,it exhibits tunable emission characteristics and promising LED performance,showcasing a color rendering index(CRI)of 78 and a correlated color temperature of 3384 K.The emitted light undergoes minimal deviation in color towards the white end of the spectrum in the temperature range of 277-437 K,making it an ideal candidate for advanced WLED applications.展开更多
Available online Integrating transition metal centered MOFs with conductive materials is a feasible route to enhance electron transfer efficiency of materials.Herein,a composite porous structure CQDs_(10)@NiFe-MOF-A w...Available online Integrating transition metal centered MOFs with conductive materials is a feasible route to enhance electron transfer efficiency of materials.Herein,a composite porous structure CQDs_(10)@NiFe-MOF-A was fabricated via introducing carbon quantum dots(CQDs)into porous NiFe-MOF.The CQDs would make partial loss of lattice in MOF during its growth,leading to the composite building block with the coexistance of crystalline region and amorphous region.The calcining treatment would produce an ultrathin protective layer as well as some lattice collapse.The synergy effect between NiFe ions effectively regulated electronic structure of metal active sites,and successful grafting of CQDs to NiFe-MOF significantly improved electrical conductivity.As expected,the catalyst exhibited outstanding OER performances with high mass activity of 91.6 A/g at overpotential of 300 mV and robust durability of 10,000 cycles in 1 mol/L KOH,which outperformed that of noble catalyst IrO_(2)of 25.2 A/g.The strategy paves a feasible and effective avenue for the non-noble metal catalysts.展开更多
Photocatalytic dual-functional reaction under visible light irradiation represents a sustainable development strategy.In detail,H2production coupled with benzylamine oxidation can remarkably lower the cost by replacin...Photocatalytic dual-functional reaction under visible light irradiation represents a sustainable development strategy.In detail,H2production coupled with benzylamine oxidation can remarkably lower the cost by replacing sacrificial agents.In this work,Cd S quantum dots(Cd S QDs)were successfully loaded onto the surface of a porphyrinic metal-organic framework(Pd-PCN-222)by the electrostatic selfassembly at room temperature.The consequent Pd-PCN-222/CdS heterojunction composites displayed superb photocatalytic activity under visible light irradiation,achieving a H2production and benzylamine oxidation rate of 5069 and 3717μmol g^(-1)h^(-1)with>99%selectivity in 3 h.There is no noticeable loss of catalytic capability during three successive runs.Mechanistic studies by in situ electron spin resonance and X-ray photoelectron spectroscopy disclosed that CdS QDs injected photoexcited electrons to Pd-PCN-222 and then Zr6clusters under visible-light irradiation,and thus Cd S QDs and Zr6clusters behave as the photocatalytic oxidation and reduction centers,respectively.展开更多
The presence of toxic mercury (Ⅱ) in water is an ever-growing problem on earth that has various harmful effect on human health and aquatic living organisms.Therefore,detection of mercury (Ⅱ) in water is very much cr...The presence of toxic mercury (Ⅱ) in water is an ever-growing problem on earth that has various harmful effect on human health and aquatic living organisms.Therefore,detection of mercury (Ⅱ) in water is very much crucial and several researches are going on in this topic.Metal-organic frameworks (MOFs) are considered as an effective device for sensing of toxic heavy metal ions in water.The tunable functionalities with large surface area of highly semiconducting MOFs enhance its activity towards fluorescence sensing.In this study,we are reporting one highly selective and sensitive luminescent sensor for the detection of mercury (Ⅱ) in water.A series of binary MOF composites were synthesized using in-situ solvothermal synthetic technique for fluorescence sensing of Hg^(2+)in water.The welldistributed graphitic carbon nitride quantum dots on porous zirconium-based MOF improve Hg^(2+)sensing activity in water owing to their great electronic and optical properties.The binary MOF composite (2) i.e.,the sensor exhibited excellent limit of detection (LOD) value of 2.4 nmol/L for Hg^(2+).The sensor also exhibited excellent performance for mercury (Ⅱ)detection in real water samples.The characterizations of the synthesized materials were done using various spectroscopic techniques and the fluorescence sensing mechanism was studied.展开更多
According to the Parikh–Wilczek tunneling framework, the locations of the local horizons of dynamic rotating black holes can be worked out. The calculations show that the quantum ergosphere of the black hole is ident...According to the Parikh–Wilczek tunneling framework, the locations of the local horizons of dynamic rotating black holes can be worked out. The calculations show that the quantum ergosphere of the black hole is identical with the tunneling potential barrier set by particle’s tunneling across the relevant horizon. Then, some discussions on the origin of the Hawking radiation will be shown.展开更多
According to the Parikh-Wilczek tunneling framework, the locations of the local horizons of dynamic rotating black holes can be worked out. The calculations show that the quantum ergosphere of the black hole is identi...According to the Parikh-Wilczek tunneling framework, the locations of the local horizons of dynamic rotating black holes can be worked out. The calculations show that the quantum ergosphere of the black hole is identical with the tunneling potential barrier set by particle's tunneling across the relevant horizon. Then, some discussions on the origin of the Hawking radiation will be shown.展开更多
The hybrid metal-organic framework [(CH3)2NH2]Fe(HCOO)3 with a perovskite-like structure exhibits a variety of unusual magnetic behaviors at low temperatures. While the long-distance super-exchange through the Fe-...The hybrid metal-organic framework [(CH3)2NH2]Fe(HCOO)3 with a perovskite-like structure exhibits a variety of unusual magnetic behaviors at low temperatures. While the long-distance super-exchange through the Fe-(Y-CH-O- Fe exchange path leads to a canted antiferromagnetic ordering at TN - 19 K, a second transition of magnetic blocking develops at TB- 9 K. The stair-shaped magnetization hysteresis loops below TB resemble the behaviors of resonant quantum tunneling of magnetization in single-molecular quantum magnets. Moreover, the magnetic relaxation also exhibits several features of resonant quantum relaxation, such as the exponential law with a single characteristic relaxation time, and the nonmonotonic dependence of relaxation rate on the applied magnetic field with a much faster relaxation around the resonant fields. The origin of quantum tunneling behaviors in the [(CH3)2NH2]Fe(HCOO)3 metal-organic framework is discussed in terms of magnetic phase separation due to the modification of hydrogen bonding on the long-distance super-exchange interaction.展开更多
Quantum algorithms have demonstrated provable speedups over classical counterparts,yet establishing a comprehensive theoretical framework to understand the quantum advantage remains a core challenge.In this work,we de...Quantum algorithms have demonstrated provable speedups over classical counterparts,yet establishing a comprehensive theoretical framework to understand the quantum advantage remains a core challenge.In this work,we decode the quantum search advantage by investigating the critical role of quantum state properties in random-walk-based algorithms.We propose three distinct variants of quantum random-walk search algorithms and derive exact analytical expressions for their success probabilities.These probabilities are fundamentally determined by specific initial state properties:the coherence fraction governs the first algorithm’s performance,while entanglement and coherence dominate the outcomes of the second and third algorithms,respectively.We show that increased coherence fraction enhances success probability,but greater entanglement and coherence reduce it in the latter two cases.These findings reveal fundamental insights into harnessing quantum properties for advantage and guide algorithm design.Our searches achieve Grover-like speedups and show significant potential for quantum-enhanced machine learning.展开更多
We present a robust quantum optimal control framework for implementing fast entangling gates on ion-trap quantum processors.The framework leverages tailored laser pulses to drive the multiple vibrational sidebands of ...We present a robust quantum optimal control framework for implementing fast entangling gates on ion-trap quantum processors.The framework leverages tailored laser pulses to drive the multiple vibrational sidebands of the ions to create phonon-mediated entangling gates and,unlike the state of the art,requires neither weakcoupling Lamb-Dicke approximation nor perturbation treatment.With the application of gradient-based optimal control,it enables finding amplitude-and phase-modulated laser control protocols that work without the Lamb-Dicke approximation,promising gate speeds on the order of microseconds comparable to the characteristic trap frequencies.Also,robustness requirements on the temperature of the ions and initial optical phase can be conveniently included to pursue high-quality fast gates against experimental imperfections.Our approach represents a step in speeding up quantum gates to achieve larger quantum circuits for quantum computation and simulation,and thus can find applications in near-future experiments.展开更多
Imines play a pivotal role as multifunctional intermediates in pharmaceutical and biological applications,and their selective synthesis under mild conditions has attracted increasing interest.In this study,a covalent-...Imines play a pivotal role as multifunctional intermediates in pharmaceutical and biological applications,and their selective synthesis under mild conditions has attracted increasing interest.In this study,a covalent-organic frameworks(COFs)modified with CeO_(2)quantum dots(QDs)were prepared through a simple chemical reaction using LZU1 COFs and Ce(NO_(3))_(3)·6H_(2)O serving as precursors.The optimized5CeO_(2)QDs@LZU1 decorated with about 3.9 wt%CeO_(2)QDs demonstrates excellent performance in the photocatalytic selective oxidative of amines in visible light conditions,achieving nearly 100%benzylamine conversion and over 99%imine selectivity within 6 h,which is significantly superior to that of pure LZU1 and CeO_(2).The remarkable enhancement in activity is mainly attributed to the fact that the interaction between CeO_(2)QDs and LZU1 COF in 5CeO_(2)QDs@LZU1 improves the visible light response and concurrently promotes the separation efficiency of photogenerated e-and h+pairs.Broad substrate scope also provides a prospect for the industrial synthesis of various imines.Our findings not only expand the application range of COFs by incorporating QDs but also lay the groundwork for their further rational design and optimization.展开更多
Classical Correlations were founded in 1900 by Karl Pearson and have since been applied as a statistical tool in virtually all sciences. Quantum correlations go back to Albert Einstein et al. in 1935 and Erwin Schr...Classical Correlations were founded in 1900 by Karl Pearson and have since been applied as a statistical tool in virtually all sciences. Quantum correlations go back to Albert Einstein et al. in 1935 and Erwin Schrödinger’s responses shortly after. In this paper, we contrast classical with quantum correlations. We find that classical correlations are weaker than quantum correlations in the CHSH framework. With respect to correlation matrices, the trace of classical correlation matrices is dissimilar to quantum density matrices. However, the off-diagonal terms have equivalent interpretations. We contrast classical dynamic (i.e., time evolving) stochastic correlation with dynamic quantum density matrices and find that the off-diagonal elements, while different in nature, have similar interpretations. So far, due to the laws of quantum physics, no classical correlations are applied to the quantum spectrum. However, conversely, quantum correlations are applied in classical environments such as quantum computing, cryptography, metrology, teleportation, medical imaging, laser technology, the quantum Internet and more.展开更多
Nanoadditives offer a promising way to reduce friction and wear.In this study,an organic-inorganic hybrid material composed of MXene quantum dots(MQDs)and cetyl trimethylammonium bromide decorated covalent organic fra...Nanoadditives offer a promising way to reduce friction and wear.In this study,an organic-inorganic hybrid material composed of MXene quantum dots(MQDs)and cetyl trimethylammonium bromide decorated covalent organic frameworks(CNUS-2)is successfully constructed via an electrostatic self-assembly strategy.The combination of MQDs and CNUS-2 not only increases the interlayer spacing of NUS-2 but also mitigates the self-aggregation of MQDs,maximizing the advantages of their intrinsic characteristics.Owing to the synergistic lubrication effect of zero-dimensional MQDs and two-dimensional NUS-2,improved lubricity and interfacial bonding ability are realized.In addition,the relative slip between the CNUS-2@MQDs sheets can reduce friction and anti-wear.As expected,different levels of CNUS-2@MQDs effectively boost the tribological properties.The friction coefficient(0.097)and wear volume(1.48×10^(5)µm^(3))of PAO-10 oil are reduced by 46.7%and 92.6%respectively,after the introduction of the 3.0 wt%CNUS-2@MQDs nanocomposite.Furthermore,the abundant oxygen-containing functional groups in CNUS-2 can accelerate the formation of adsorption and tribochemical reaction films,whereas the MQDs can repair worn surfaces,resulting in superior lubrication performance under variable load,temperature,and frequency conditions.This work not only effectively improves lubrication performance by developing a unique CNUS-2@MQDs nanocomposite,but also provides a reference for the design of novel lubricant additives.展开更多
基金funded by Shanghai Pujiang Program(21PJD022)Hunan Provincial Natural Science Foundation(2023JJ60522).
文摘Balancing the adsorption of OH⁻and 5-hydroxymethylfurfural(HMF)is crucial in optimizing the competing HMF oxidation reaction and oxygen evolution reaction,especially given the polymerization tendency of HMF in alkaline solutions.Herein,we present an innovative approach for rapidly synthesizing a NiFe bimetallic metalorganic framework(MOF)induced by electron-withdrawing carbon quantum dot(EW-CQD)via electron beam irradiation within 2 min.EW-CQD serve as structural regulators,expanding the NiFe-MOF interlayer spacing,increasing reactive site availability,and more effectively balancing the adsorption of OH6(-) and HMF,thereby significantly boosting the oxidation activity of HMF.The resulting EW-CQD-MOF exhibits a low potential of 1.36 V vs.RHE at 10 mA cm^(-2)and maintains excellent durability over 120 h.Comprehensive in situ characterization elucidates the HMF oxidation reaction pathway,showing high selectivity towards 2,5-furandicarboxylic acid(FDCA)under ambient conditions,with an impressive HMF conversion rate of 94%and FDCA selectivity of 96%within 6 h.These findings underscore the critical role of structural optimization and adsorption balance in catalytic performance enhancement and offer valuable insights for designing high-efficiency catalysts,advancing sustainable catalytic processes.
基金financial support of National Key Research and Development Program of China(No.2021YFA1501500)the National Natural Science Foundation of China(Nos.22033008,22220102005,22171265)Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(No.2021ZZ103).
文摘The growing environmental concerns regarding rare earth elements in fluorescent powders,along with high production costs,have increased the demand for sustainable alternatives.We propose a promising solution using luminescent metal-organic frameworks(LMOFs)with large surface areas and tunable pore structures,combined with organic carbon quantum dots(CQDs).This study develops a novel white lightemitting diode(WLED)fluorescent powder by incorporating yellow-fluorescent quantum dots(CQDs-Y)into blue-emitting LMOF(ZJU-28),forming the composite material CQDs-Y-n@ZJU-28.The composite exhibits excellent thermal and chemical stability,long-term storage performance,and emits warm white light(CIE:0.3277,0.3281)when subjected to excitation at 365 nm,along with an external quantum efficiency(EQE)of 8.85%.Furthermore,it exhibits tunable emission characteristics and promising LED performance,showcasing a color rendering index(CRI)of 78 and a correlated color temperature of 3384 K.The emitted light undergoes minimal deviation in color towards the white end of the spectrum in the temperature range of 277-437 K,making it an ideal candidate for advanced WLED applications.
基金financially supported by the Fundamental Research Funds for the Central Universities(No.2042021kf0077)Start-up funds for provincial and municipal"double first-class"construction special talents(No.600460001)China postdoctoral Science Foundation(No.2017M612496)。
文摘Available online Integrating transition metal centered MOFs with conductive materials is a feasible route to enhance electron transfer efficiency of materials.Herein,a composite porous structure CQDs_(10)@NiFe-MOF-A was fabricated via introducing carbon quantum dots(CQDs)into porous NiFe-MOF.The CQDs would make partial loss of lattice in MOF during its growth,leading to the composite building block with the coexistance of crystalline region and amorphous region.The calcining treatment would produce an ultrathin protective layer as well as some lattice collapse.The synergy effect between NiFe ions effectively regulated electronic structure of metal active sites,and successful grafting of CQDs to NiFe-MOF significantly improved electrical conductivity.As expected,the catalyst exhibited outstanding OER performances with high mass activity of 91.6 A/g at overpotential of 300 mV and robust durability of 10,000 cycles in 1 mol/L KOH,which outperformed that of noble catalyst IrO_(2)of 25.2 A/g.The strategy paves a feasible and effective avenue for the non-noble metal catalysts.
基金support from the National Natural Science Foundation of China(Nos.21773314,21821003 and 21890382)the Guangdong Natural Science Funds for Distinguished Young Scholar(No.2019B151502017)。
文摘Photocatalytic dual-functional reaction under visible light irradiation represents a sustainable development strategy.In detail,H2production coupled with benzylamine oxidation can remarkably lower the cost by replacing sacrificial agents.In this work,Cd S quantum dots(Cd S QDs)were successfully loaded onto the surface of a porphyrinic metal-organic framework(Pd-PCN-222)by the electrostatic selfassembly at room temperature.The consequent Pd-PCN-222/CdS heterojunction composites displayed superb photocatalytic activity under visible light irradiation,achieving a H2production and benzylamine oxidation rate of 5069 and 3717μmol g^(-1)h^(-1)with>99%selectivity in 3 h.There is no noticeable loss of catalytic capability during three successive runs.Mechanistic studies by in situ electron spin resonance and X-ray photoelectron spectroscopy disclosed that CdS QDs injected photoexcited electrons to Pd-PCN-222 and then Zr6clusters under visible-light irradiation,and thus Cd S QDs and Zr6clusters behave as the photocatalytic oxidation and reduction centers,respectively.
文摘The presence of toxic mercury (Ⅱ) in water is an ever-growing problem on earth that has various harmful effect on human health and aquatic living organisms.Therefore,detection of mercury (Ⅱ) in water is very much crucial and several researches are going on in this topic.Metal-organic frameworks (MOFs) are considered as an effective device for sensing of toxic heavy metal ions in water.The tunable functionalities with large surface area of highly semiconducting MOFs enhance its activity towards fluorescence sensing.In this study,we are reporting one highly selective and sensitive luminescent sensor for the detection of mercury (Ⅱ) in water.A series of binary MOF composites were synthesized using in-situ solvothermal synthetic technique for fluorescence sensing of Hg^(2+)in water.The welldistributed graphitic carbon nitride quantum dots on porous zirconium-based MOF improve Hg^(2+)sensing activity in water owing to their great electronic and optical properties.The binary MOF composite (2) i.e.,the sensor exhibited excellent limit of detection (LOD) value of 2.4 nmol/L for Hg^(2+).The sensor also exhibited excellent performance for mercury (Ⅱ)detection in real water samples.The characterizations of the synthesized materials were done using various spectroscopic techniques and the fluorescence sensing mechanism was studied.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 10873003 and 10633010)the National Basic Research Program of China (Grant No. 2007CB815405)+1 种基金the Bureau of Education of Guangzhou Municipality, China (Grant No. 11 Sui-Jiao-Ke[2009])the Guangdong Province Universities and Colleges Pearl River Scholar Funded Scheme (Grant No. 2009)
文摘According to the Parikh–Wilczek tunneling framework, the locations of the local horizons of dynamic rotating black holes can be worked out. The calculations show that the quantum ergosphere of the black hole is identical with the tunneling potential barrier set by particle’s tunneling across the relevant horizon. Then, some discussions on the origin of the Hawking radiation will be shown.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 10873003 and 10633010)the National Basic Research Program of China (Grant No. 2007CB815405)+1 种基金the Bureau of Education of Guangzhou Municipality, China (Grant No. 11 Sui-Jiao-Ke[2009])the Guangdong Province Universities and Colleges Pearl River Scholar Funded Scheme (Grant No. 2009)
文摘According to the Parikh-Wilczek tunneling framework, the locations of the local horizons of dynamic rotating black holes can be worked out. The calculations show that the quantum ergosphere of the black hole is identical with the tunneling potential barrier set by particle's tunneling across the relevant horizon. Then, some discussions on the origin of the Hawking radiation will be shown.
基金supported by the National Natural Science Foundation of China(Grant Nos.11227405,51371192,and 51371193)the Chinese Academy of Sciences(Grant No.XDB07030200)
文摘The hybrid metal-organic framework [(CH3)2NH2]Fe(HCOO)3 with a perovskite-like structure exhibits a variety of unusual magnetic behaviors at low temperatures. While the long-distance super-exchange through the Fe-(Y-CH-O- Fe exchange path leads to a canted antiferromagnetic ordering at TN - 19 K, a second transition of magnetic blocking develops at TB- 9 K. The stair-shaped magnetization hysteresis loops below TB resemble the behaviors of resonant quantum tunneling of magnetization in single-molecular quantum magnets. Moreover, the magnetic relaxation also exhibits several features of resonant quantum relaxation, such as the exponential law with a single characteristic relaxation time, and the nonmonotonic dependence of relaxation rate on the applied magnetic field with a much faster relaxation around the resonant fields. The origin of quantum tunneling behaviors in the [(CH3)2NH2]Fe(HCOO)3 metal-organic framework is discussed in terms of magnetic phase separation due to the modification of hydrogen bonding on the long-distance super-exchange interaction.
基金supported by the Fundamental Research Funds for the Central Universities,the National Natural Science Foundation of China(Grant Nos.12371132,12075159,12171044,12071179,and 12405006)the specific research fund of the Innovation Platform for Academicians of Hainan Province.
文摘Quantum algorithms have demonstrated provable speedups over classical counterparts,yet establishing a comprehensive theoretical framework to understand the quantum advantage remains a core challenge.In this work,we decode the quantum search advantage by investigating the critical role of quantum state properties in random-walk-based algorithms.We propose three distinct variants of quantum random-walk search algorithms and derive exact analytical expressions for their success probabilities.These probabilities are fundamentally determined by specific initial state properties:the coherence fraction governs the first algorithm’s performance,while entanglement and coherence dominate the outcomes of the second and third algorithms,respectively.We show that increased coherence fraction enhances success probability,but greater entanglement and coherence reduce it in the latter two cases.These findings reveal fundamental insights into harnessing quantum properties for advantage and guide algorithm design.Our searches achieve Grover-like speedups and show significant potential for quantum-enhanced machine learning.
基金supported by the National Natural Science Foundation of China(Grant Nos.12441502,12122506,12204230,and 12404554)the National Science and Technology Major Project of the Ministry of Science and Technology of China(2024ZD0300404)+6 种基金Guangdong Basic and Applied Basic Research Foundation(Grant No.2021B1515020070)Shenzhen Science and Technology Program(Grant No.RCYX20200714114522109)China Postdoctoral Science Foundation(CPSF)(2024M762114)Postdoctoral Fellowship Program of CPSF(GZC20231727)supported by the National Natural Science Foundation of China(Grant Nos.92165206 and 11974330)Innovation Program for Quantum Science and Technology(Grant No.2021ZD0301603)the Fundamental Research Funds for the Central Universities。
文摘We present a robust quantum optimal control framework for implementing fast entangling gates on ion-trap quantum processors.The framework leverages tailored laser pulses to drive the multiple vibrational sidebands of the ions to create phonon-mediated entangling gates and,unlike the state of the art,requires neither weakcoupling Lamb-Dicke approximation nor perturbation treatment.With the application of gradient-based optimal control,it enables finding amplitude-and phase-modulated laser control protocols that work without the Lamb-Dicke approximation,promising gate speeds on the order of microseconds comparable to the characteristic trap frequencies.Also,robustness requirements on the temperature of the ions and initial optical phase can be conveniently included to pursue high-quality fast gates against experimental imperfections.Our approach represents a step in speeding up quantum gates to achieve larger quantum circuits for quantum computation and simulation,and thus can find applications in near-future experiments.
基金Project supported by the National Natural Science Foundation of China(22176054,22306060)China Postdoctoral Science Foundation(2022M721134)the Fundamental Research Funds for the Central Universities(2023MS060)。
文摘Imines play a pivotal role as multifunctional intermediates in pharmaceutical and biological applications,and their selective synthesis under mild conditions has attracted increasing interest.In this study,a covalent-organic frameworks(COFs)modified with CeO_(2)quantum dots(QDs)were prepared through a simple chemical reaction using LZU1 COFs and Ce(NO_(3))_(3)·6H_(2)O serving as precursors.The optimized5CeO_(2)QDs@LZU1 decorated with about 3.9 wt%CeO_(2)QDs demonstrates excellent performance in the photocatalytic selective oxidative of amines in visible light conditions,achieving nearly 100%benzylamine conversion and over 99%imine selectivity within 6 h,which is significantly superior to that of pure LZU1 and CeO_(2).The remarkable enhancement in activity is mainly attributed to the fact that the interaction between CeO_(2)QDs and LZU1 COF in 5CeO_(2)QDs@LZU1 improves the visible light response and concurrently promotes the separation efficiency of photogenerated e-and h+pairs.Broad substrate scope also provides a prospect for the industrial synthesis of various imines.Our findings not only expand the application range of COFs by incorporating QDs but also lay the groundwork for their further rational design and optimization.
文摘Classical Correlations were founded in 1900 by Karl Pearson and have since been applied as a statistical tool in virtually all sciences. Quantum correlations go back to Albert Einstein et al. in 1935 and Erwin Schrödinger’s responses shortly after. In this paper, we contrast classical with quantum correlations. We find that classical correlations are weaker than quantum correlations in the CHSH framework. With respect to correlation matrices, the trace of classical correlation matrices is dissimilar to quantum density matrices. However, the off-diagonal terms have equivalent interpretations. We contrast classical dynamic (i.e., time evolving) stochastic correlation with dynamic quantum density matrices and find that the off-diagonal elements, while different in nature, have similar interpretations. So far, due to the laws of quantum physics, no classical correlations are applied to the quantum spectrum. However, conversely, quantum correlations are applied in classical environments such as quantum computing, cryptography, metrology, teleportation, medical imaging, laser technology, the quantum Internet and more.
基金supported by the National Natural Science Foundation of China(22109127)the China Postdoctoral Science Foundation(2021M702666)+1 种基金the Youth Project of"Shaanxi High-level Talents Introduction Plan",the Research Fund of the State Key Laboratory of Solidification Processing(NPU),China(2023-TS-02)the"Special Lubrication and Sealing for Aerospace"Shaanxi Provincial Science and Technology Innovation Team(2024RS-CXTD-63)。
文摘Nanoadditives offer a promising way to reduce friction and wear.In this study,an organic-inorganic hybrid material composed of MXene quantum dots(MQDs)and cetyl trimethylammonium bromide decorated covalent organic frameworks(CNUS-2)is successfully constructed via an electrostatic self-assembly strategy.The combination of MQDs and CNUS-2 not only increases the interlayer spacing of NUS-2 but also mitigates the self-aggregation of MQDs,maximizing the advantages of their intrinsic characteristics.Owing to the synergistic lubrication effect of zero-dimensional MQDs and two-dimensional NUS-2,improved lubricity and interfacial bonding ability are realized.In addition,the relative slip between the CNUS-2@MQDs sheets can reduce friction and anti-wear.As expected,different levels of CNUS-2@MQDs effectively boost the tribological properties.The friction coefficient(0.097)and wear volume(1.48×10^(5)µm^(3))of PAO-10 oil are reduced by 46.7%and 92.6%respectively,after the introduction of the 3.0 wt%CNUS-2@MQDs nanocomposite.Furthermore,the abundant oxygen-containing functional groups in CNUS-2 can accelerate the formation of adsorption and tribochemical reaction films,whereas the MQDs can repair worn surfaces,resulting in superior lubrication performance under variable load,temperature,and frequency conditions.This work not only effectively improves lubrication performance by developing a unique CNUS-2@MQDs nanocomposite,but also provides a reference for the design of novel lubricant additives.