Classical computation of electronic properties in large-scale materials remains challenging.Quantum computation has the potential to offer advantages in memory footprint and computational scaling.However,general and v...Classical computation of electronic properties in large-scale materials remains challenging.Quantum computation has the potential to offer advantages in memory footprint and computational scaling.However,general and viable quantum algorithms for simulating large-scale materials are still limited.We propose and implement random-state quantum algorithms to calculate electronic-structure properties of real materials.Using a random state circuit on a small number of qubits,we employ real-time evolution with first-order Trotter decomposition and Hadamard test to obtain electronic density of states,and we develop a modified quantum phase estimation algorithm to calculate real-space local density of states via direct quantum measurements.Furthermore,we validate these algorithms by numerically computing the density of states and spatial distributions of electronic states in graphene,twisted bilayer graphene quasicrystals,and fractal lattices,covering system sizes from hundreds to thousands of atoms.Our results manifest that the random-state quantum algorithms provide a general and qubit-efficient route to scalable simulations of electronic properties in large-scale periodic and aperiodic materials.展开更多
The development of quantum materials for single-photon emission is crucial for the advancement of quantum information technology.Although significant advancements have been witnessed in recent years for single-photon ...The development of quantum materials for single-photon emission is crucial for the advancement of quantum information technology.Although significant advancements have been witnessed in recent years for single-photon sources in the near-infrared band(λ∼700–1000 nm),several challenges have yet to be addressed for ideal single-photon emission at the telecommunication band.In this study,we present a droplet-epitaxy strategy for O-band to C-band single-photon source-based semiconductor quantum dots(QDs)using metal-organic vaporphase epitaxy(MOVPE).By investigating the growth conditions of the epitaxial process,we have successfully synthesized InAs/InP QDs with narrow emission lines spanning a broad spectral range of λ∼1200–1600 nm.The morphological and optical properties of the samples were characterized using atomic force microscopy and microphotoluminescence spectroscopy.The recorded single-photon purity of a plain QD structure reaches g^((2))(0)=0.16,with a radiative recombination lifetime as short as 1.5 ns.This work provides a crucial platform for future research on integrated microcavity enhancement techniques and coupled QDs with other quantum photonics in the telecom bands,offering significant prospects for quantum network applications.展开更多
The hybridization gap in strained-layer InAs/In_(x)Ga_(1−x) Sb quantum spin Hall insulators(QSHIs)is significantly enhanced compared to binary InAs/GaSb QSHI structures,where the typical indium composition,x,ranges be...The hybridization gap in strained-layer InAs/In_(x)Ga_(1−x) Sb quantum spin Hall insulators(QSHIs)is significantly enhanced compared to binary InAs/GaSb QSHI structures,where the typical indium composition,x,ranges between 0.2 and 0.4.This enhancement prompts a critical question:to what extent can quantum wells(QWs)be strained while still preserving the fundamental QSHI phase?In this study,we demonstrate the controlled molecular beam epitaxial growth of highly strained-layer QWs with an indium composition of x=0.5.These structures possess a substantial compressive strain within the In_(0.5)Ga_(0.5)Sb QW.Detailed crystal structure analyses confirm the exceptional quality of the resulting epitaxial films,indicating coherent lattice structures and the absence of visible dislocations.Transport measurements further reveal that the QSHI phase in InAs/In_(0.5)Ga_(0.5)Sb QWs is robust and protected by time-reversal symmetry.Notably,the edge states in these systems exhibit giant magnetoresistance when subjected to a modest perpendicular magnetic field.This behavior is in agreement with the𝑍2 topological property predicted by the Bernevig–Hughes–Zhang model,confirming the preservation of topologically protected edge transport in the presence of enhanced bulk strain.展开更多
Data security has become a growing priority due to the increasing frequency of cyber-attacks,necessitating the development of more advanced encryption algorithms.This paper introduces Single Qubit Quantum Logistic-Sin...Data security has become a growing priority due to the increasing frequency of cyber-attacks,necessitating the development of more advanced encryption algorithms.This paper introduces Single Qubit Quantum Logistic-Sine XYZ-Rotation Maps(SQQLSR),a quantum-based chaos map designed to generate one-dimensional chaotic sequences with an ultra-wide parameter range.The proposed model leverages quantum superposition using Hadamard gates and quantum rotations along the X,Y,and Z axes to enhance randomness.Extensive numerical experiments validate the effectiveness of SQQLSR.The proposed method achieves a maximum Lyapunov exponent(LE)of≈55.265,surpassing traditional chaotic maps in unpredictability.The bifurcation analysis confirms a uniform chaotic distribution,eliminating periodic windows and ensuring higher randomness.The system also generates an expanded key space exceeding 10^(40),enhancing security against brute-force attacks.Additionally,SQQLSR is applied to image encryption using a simple three-layer encryption scheme combining permutation and substitution techniques.This approach is intentionally designed to highlight the impact of SQQLSR-generated chaotic sequences rather than relying on a complex encryption algorithm.Theencryption method achieves an average entropy of 7.9994,NPCR above 99.6%,and UACI within 32.8%–33.8%,confirming its strong randomness and sensitivity to minor modifications.The robustness tests against noise,cropping,and JPEG compression demonstrate its resistance to statistical and differential attacks.Additionally,the decryption process ensures perfect image reconstruction with an infinite PSNR value,proving the algorithm’s reliability.These results highlight SQQLSR’s potential as a lightweight yet highly secure encryption mechanism suitable for quantum cryptography and secure communications.展开更多
InP quantum dots(QDs)have been a major building block of modern display technology due to their high photoluminescence quantum yield(PLQY)in the visible spectrum,superior stability,and eco-friendly composition.However...InP quantum dots(QDs)have been a major building block of modern display technology due to their high photoluminescence quantum yield(PLQY)in the visible spectrum,superior stability,and eco-friendly composition.However,their applications at short-wave infrared(SWIR)have been hindered by their low efficiency.Here,we report the synthesis of efficient and SWIR-emitting InP QDs by precisely controlling the InP core nucleation using a low-cost ammonia phosphorus precursor,while avoiding size-limiting ZnCl_(2) for effective copper doping.Subsequent epitaxial growth of a lattice-matched ZnSe/ZnS multishell enhanced the QD sphericity and surface smoothness and yielded a record PLQY of 66% with an emission peak at 960 nm.When QDs were integrated as the high-refractive-index luminescent core of a liquid waveguide-based luminescent solar concentrator(LSC),the device achieved an optical efficiency of 7.36%.This performance arises from their high PLQY,spectral alignment with the responsivity peak of silicon solar cells,and the optimized core/cladding waveguide structure.These results highlight the potential of InP QDs as a promising nanomaterial for SWIR emission and applications.展开更多
To fully utilize the resources provided by optical fiber networks,a cross-band quantum light source generating photon pairs,where one photon in a pair is at C band and the other is at O band,is proposed in this work.T...To fully utilize the resources provided by optical fiber networks,a cross-band quantum light source generating photon pairs,where one photon in a pair is at C band and the other is at O band,is proposed in this work.This source is based on spontaneous four-wave mixing(SFWM)in a piece of shallow-ridge silicon waveguide.Theoretical analysis shows that the waveguide dispersion could be tailored by adjusting the ridge width,enabling broadband photon pair generation by SFWM across C band and O band.The spontaneous Raman scattering(SpRS)in silicon waveguides is also investigated experimentally.It shows that there are two regions in the spectrum of generated photons from SpRS,which could be used to achieve cross-band photon pair generation.A chip of shallow-ridge silicon waveguide samples with different ridge widths has been fabricated,through which cross-band photon pair generation is demonstrated experimentally.The experimental results show that the source can be achieved using dispersion-optimized shallow-ridge silicon waveguides.This cross-band quantum light source provides a way to develop new fiber-based quantum communication functions utilizing both C band and O band and extends applications of quantum networks.展开更多
We propose a quantum Otto engine operating through a cycle of two isochoric processes,where the working substance interacts with a single-mode radiation field,and two unitary strokes,during which the working substance...We propose a quantum Otto engine operating through a cycle of two isochoric processes,where the working substance interacts with a single-mode radiation field,and two unitary strokes,during which the working substance is decoupled from the field.We investigate the influence of quantum superposition and quantum internal friction on the engine's power output and efficiency,demonstrating that these quantum effects enhance both performance metrics.While these enhancements are accompanied by increased power fluctuations,we show that such fluctuations can be effectively mitigated through careful selection of control parameters.Our results reveal that the proposed quantum Otto engine can achieve performance regimes that are thermally inconceivable in classical systems,including surpassing the Otto efficiency limit and attaining 100%efficiency with nonzero power output.展开更多
On May 9,2025 on the campus of the University of Science and Technology of China(USTC),Chinese Academy of Sciences(CAS),an exhibition was unveiled to celebrate the UN International Year of Quantum Science and Technolo...On May 9,2025 on the campus of the University of Science and Technology of China(USTC),Chinese Academy of Sciences(CAS),an exhibition was unveiled to celebrate the UN International Year of Quantum Science and Technology(IYQ)-a one-year-long worldwide event in memory of the founding of quantum mechanics(QM).展开更多
Quantum photonic integrated circuits offer enhanced stability and scalability for quantum communications,sensing, and computing. Transverse modes in multimode waveguides enable high-dimensional scalability and versati...Quantum photonic integrated circuits offer enhanced stability and scalability for quantum communications,sensing, and computing. Transverse modes in multimode waveguides enable high-dimensional scalability and versatile photon manipulation, but practical adoption requires compact and fabrication-tolerant quantum interference devices. Here, we present an ultra-compact taper-stepped beamsplitter that enables quantum interference between photon pairs in different transverse modes, and cascade it to realize NOON state interferometry. We experimentally achieve high visibilities of 93.9% for HOM interference and 86.5% for NOON state interference,demonstrating that efficient mode interference with active tuning can be realized on this platform.展开更多
Entanglement asymmetry(EA) has emerged as a powerful tool for characterizing symmetry breaking in quantum many-body systems. In this Letter, we explore how symmetry is dynamically broken through the lens of EA in two ...Entanglement asymmetry(EA) has emerged as a powerful tool for characterizing symmetry breaking in quantum many-body systems. In this Letter, we explore how symmetry is dynamically broken through the lens of EA in two distinct scenarios: a non-symmetric Hamiltonian quench and a non-symmetric random quantum circuit, with a particular focus on U(1) symmetry. In the former case, symmetry remains broken in the subsystem at late times, whereas in the latter case, the symmetry is initially broken and subsequently restored, consistent with the principles of quantum thermalization. Notably, the growth of EA exhibits unexpected overshooting behavior at early times in both contexts, contrasting with the behavior of charge variance. We also consider dynamics of non-symmetric initial states under the symmetry-breaking evolution. Due to the competition of symmetry-breaking in both the initial state and Hamiltonian, the early-time EA can increase and decrease, while quantum Mpemba effects remain evident despite the weak symmetry-breaking in both settings.展开更多
Quantum integrability provides a unique and powerful framework for accurately understanding quantum magnetism.In this review,we focus specifically on several quantum integrable low-dimensional quantum Ising models.We ...Quantum integrability provides a unique and powerful framework for accurately understanding quantum magnetism.In this review,we focus specifically on several quantum integrable low-dimensional quantum Ising models.We begin with the transverse field Ising chain(TFIC)at quantum critical point and examine how it evolves under perturbations,such as an applied longitudinal field or weak coupling to another quantum critical TFIC.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
The quantum hybrid algorithm has recently become a very promising and speedy method for solving larger-scale optimization problems in the noisy intermediate-scale quantum(NISQ)era.The unit commitment(UC)problem is a f...The quantum hybrid algorithm has recently become a very promising and speedy method for solving larger-scale optimization problems in the noisy intermediate-scale quantum(NISQ)era.The unit commitment(UC)problem is a fundamental problem in the field of power systems that aims to satisfy the power balance constraint with minimal cost.In this paper,we focus on the implementation of the UC solution using exact quantum algorithms based on the quantum neural network(QNN).This method is tested with a ten-unit system under the power balance constraint.In order to improve computing precision and reduce network complexity,we propose a knowledge-based partially connected quantum neural network(PCQNN).The results show that exact solutions can be obtained by the improved algorithm and that the depth of the quantum circuit can be reduced simultaneously.展开更多
The rapid advancement of quantum computing has sparked a considerable increase in research attention to quantum technologies.These advances span fundamental theoretical inquiries into quantum information and the explo...The rapid advancement of quantum computing has sparked a considerable increase in research attention to quantum technologies.These advances span fundamental theoretical inquiries into quantum information and the exploration of diverse applications arising from this evolving quantum computing paradigm.The scope of the related research is notably diverse.This paper consolidates and presents quantum computing research related to the financial sector.The finance applications considered in this study include portfolio optimization,fraud detection,and Monte Carlo methods for derivative pricing and risk calculation.In addition,we provide a comprehensive analysis of quantum computing’s applications and effects on blockchain technologies,particularly in relation to cryptocurrencies,which are central to financial technology research.As discussed in this study,quantum computing applications in finance are based on fundamental quantum physics principles and key quantum algorithms.This review aims to bridge the research gap between quantum computing and finance.We adopt a two-fold methodology,involving an analysis of quantum algorithms,followed by a discussion of their applications in specific financial contexts.Our study is based on an extensive review of online academic databases,search tools,online journal repositories,and whitepapers from 1952 to 2023,including CiteSeerX,DBLP,Research-Gate,Semantic Scholar,and scientific conference publications.We present state-of-theart findings at the intersection of finance and quantum technology and highlight open research questions that will be valuable for industry practitioners and academicians as they shape future research agendas.展开更多
Implementing quantum wireless multi-hop network communication is essential to improve the global quantum network system. In this paper, we employ eight-level GHZ states as quantum channels to realize multi-hop quantum...Implementing quantum wireless multi-hop network communication is essential to improve the global quantum network system. In this paper, we employ eight-level GHZ states as quantum channels to realize multi-hop quantum communication, and utilize the logical relationship between the measurements of each node to derive the unitary operation performed by the end node. The hierarchical simultaneous entanglement switching(HSES) method is adopted, resulting in a significant reduction in the consumption of classical information compared to multi-hop quantum teleportation(QT)based on general simultaneous entanglement switching(SES). In addition, the proposed protocol is simulated on the IBM Quantum Experiment platform(IBM QE). Then, the data obtained from the experiment are analyzed using quantum state tomography, which verifies the protocol's good fidelity and accuracy. Finally, by calculating fidelity, we analyze the impact of four different types of noise(phase-damping, amplitude-damping, phase-flip and bit-flip) in this protocol.展开更多
As quantum computing transitions from a theoretical domain to a practical technology, many aspects of established practice in software engineering are being faced with new challenges. Quantum Software Engineering has ...As quantum computing transitions from a theoretical domain to a practical technology, many aspects of established practice in software engineering are being faced with new challenges. Quantum Software Engineering has been developed to address the peculiar needs that arise with quantum systems’ dependable, scalable, and fault-tolerant software development. The present paper critically reviews how traditional software engineering methodologies can be reshaped to fit into the quantum field. This also entails providing some critical contributions: frameworks to integrate classical and quantum systems, new error mitigation techniques, and the development of quantum-specific testing and debugging tools. In this respect, best practices have been recommended to ensure that future quantum software can harness the evolving capabilities of quantum hardware with continued performance, reliability, and scalability. The work is supposed to act as a foundational guide for the researcher and developer as quantum computing approaches widespread scientific and industrial adoption.展开更多
In this paper, classical and continuous variable (CV) quantum neural network hybrid multi-classifiers are presented using the MNIST dataset. Currently available classifiers can classify only up to two classes. The pro...In this paper, classical and continuous variable (CV) quantum neural network hybrid multi-classifiers are presented using the MNIST dataset. Currently available classifiers can classify only up to two classes. The proposed architecture allows networks to classify classes up to n<sup>m</sup> classes, where n represents cutoff dimension and m the number of qumodes on photonic quantum computers. The combination of cutoff dimension and probability measurement method in the CV model allows a quantum circuit to produce output vectors of size n<sup>m</sup>. They are then interpreted as one-hot encoded labels, padded with n<sup>m</sup> - 10 zeros. The total of seven different classifiers is built using 2, 3, …, 6, and 8-qumodes on photonic quantum computing simulators, based on the binary classifier architecture proposed in “Continuous variable quantum neural networks” [1]. They are composed of a classical feed-forward neural network, a quantum data encoding circuit, and a CV quantum neural network circuit. On a truncated MNIST dataset of 600 samples, a 4-qumode hybrid classifier achieves 100% training accuracy.展开更多
A team of researchers from the University of Science and Technology of China(USTC)of the Chinese Academy of Sciences(CAS)and its partners have made significant advancements in random quantum circuit sampling with Zuch...A team of researchers from the University of Science and Technology of China(USTC)of the Chinese Academy of Sciences(CAS)and its partners have made significant advancements in random quantum circuit sampling with Zuchongzhi-3,a superconducting quantum computing prototype featuring 105 qubits and 182 couplers.展开更多
Quantum computing is a promising technology that has the potential to revolutionize many areas of science and technology,including communication.In this review,we discuss the current state of quantum computing in comm...Quantum computing is a promising technology that has the potential to revolutionize many areas of science and technology,including communication.In this review,we discuss the current state of quantum computing in communication and its potential applications in various areas such as network optimization,signal processing,and machine learning for communication.First,the basic principle of quantum computing,quantum physics systems,and quantum algorithms are analyzed.Then,based on the classification of quantum algorithms,several important basic quantum algorithms,quantum optimization algorithms,and quantum machine learning algorithms are discussed in detail.Finally,the basic ideas and feasibility of introducing quantum algorithms into communications are emphatically analyzed,which provides a reference to address computational bottlenecks in communication networks.展开更多
Background:Diabetic retinopathy remains one of the leading causes of vision impairment globally and poses diagnostic challenges due to the complexity of clinical imaging data and variability in disease progression.In ...Background:Diabetic retinopathy remains one of the leading causes of vision impairment globally and poses diagnostic challenges due to the complexity of clinical imaging data and variability in disease progression.In this study,we propose an innovative methodology that integrates artificial intelligence and quantum computing to enhance the early detection and clinical management of diabetic retinopathy.Methods:We developed a hybrid model combining machine learning algorithms with simulated quantum circuits to classify retinal images and associated clinical data.Anonymized datasets were used,and deep inductive transfer techniques were applied to improve diagnostic precision and generalizability.Results:The proposed model achieved a classification accuracy of 94.6%,significantly reducing diagnostic time and improving the prioritization of high-risk cases compared to conventional methods.The hybrid approach demonstrated superior performance in processing speed and accuracy for complex clinical scenarios.Conclusion:This study highlights the potential of combining AI and quantum computing to revolutionize the diagnosis of diabetic retinopathy.The proposed model provides a scalable and efficient solution for clinical environments,enabling faster and more accurate decision-making in ophthalmic care.展开更多
基金supported by the Major Project for the Integration of ScienceEducation and Industry (Grant No.2025ZDZX02)。
文摘Classical computation of electronic properties in large-scale materials remains challenging.Quantum computation has the potential to offer advantages in memory footprint and computational scaling.However,general and viable quantum algorithms for simulating large-scale materials are still limited.We propose and implement random-state quantum algorithms to calculate electronic-structure properties of real materials.Using a random state circuit on a small number of qubits,we employ real-time evolution with first-order Trotter decomposition and Hadamard test to obtain electronic density of states,and we develop a modified quantum phase estimation algorithm to calculate real-space local density of states via direct quantum measurements.Furthermore,we validate these algorithms by numerically computing the density of states and spatial distributions of electronic states in graphene,twisted bilayer graphene quasicrystals,and fractal lattices,covering system sizes from hundreds to thousands of atoms.Our results manifest that the random-state quantum algorithms provide a general and qubit-efficient route to scalable simulations of electronic properties in large-scale periodic and aperiodic materials.
基金supported by the National Natural Science Foundation of China (Grant Nos.12494604,12393834,12393831,62274014,6223501662335015)the National Key R&D Program of China (Grant No.2024YFA1208900)。
文摘The development of quantum materials for single-photon emission is crucial for the advancement of quantum information technology.Although significant advancements have been witnessed in recent years for single-photon sources in the near-infrared band(λ∼700–1000 nm),several challenges have yet to be addressed for ideal single-photon emission at the telecommunication band.In this study,we present a droplet-epitaxy strategy for O-band to C-band single-photon source-based semiconductor quantum dots(QDs)using metal-organic vaporphase epitaxy(MOVPE).By investigating the growth conditions of the epitaxial process,we have successfully synthesized InAs/InP QDs with narrow emission lines spanning a broad spectral range of λ∼1200–1600 nm.The morphological and optical properties of the samples were characterized using atomic force microscopy and microphotoluminescence spectroscopy.The recorded single-photon purity of a plain QD structure reaches g^((2))(0)=0.16,with a radiative recombination lifetime as short as 1.5 ns.This work provides a crucial platform for future research on integrated microcavity enhancement techniques and coupled QDs with other quantum photonics in the telecom bands,offering significant prospects for quantum network applications.
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences (Grant Nos.XDB28000000 and XDB0460000)the Quantum Science and Technology-National Science and Technology Major Project (Grant No.2021ZD0302600)the National Key Research and Development Program of China(Grant No.2024YFA1409002)。
文摘The hybridization gap in strained-layer InAs/In_(x)Ga_(1−x) Sb quantum spin Hall insulators(QSHIs)is significantly enhanced compared to binary InAs/GaSb QSHI structures,where the typical indium composition,x,ranges between 0.2 and 0.4.This enhancement prompts a critical question:to what extent can quantum wells(QWs)be strained while still preserving the fundamental QSHI phase?In this study,we demonstrate the controlled molecular beam epitaxial growth of highly strained-layer QWs with an indium composition of x=0.5.These structures possess a substantial compressive strain within the In_(0.5)Ga_(0.5)Sb QW.Detailed crystal structure analyses confirm the exceptional quality of the resulting epitaxial films,indicating coherent lattice structures and the absence of visible dislocations.Transport measurements further reveal that the QSHI phase in InAs/In_(0.5)Ga_(0.5)Sb QWs is robust and protected by time-reversal symmetry.Notably,the edge states in these systems exhibit giant magnetoresistance when subjected to a modest perpendicular magnetic field.This behavior is in agreement with the𝑍2 topological property predicted by the Bernevig–Hughes–Zhang model,confirming the preservation of topologically protected edge transport in the presence of enhanced bulk strain.
基金funded by Kementerian Pendidikan Tinggi,Sains,dan Teknologi(Kemdiktisaintek),Indonesia,grant numbers 108/E5/PG.02.00.PL/2024,027/LL6/PB/AL.04/2024,061/A.38-04/UDN-09/VI/2024.
文摘Data security has become a growing priority due to the increasing frequency of cyber-attacks,necessitating the development of more advanced encryption algorithms.This paper introduces Single Qubit Quantum Logistic-Sine XYZ-Rotation Maps(SQQLSR),a quantum-based chaos map designed to generate one-dimensional chaotic sequences with an ultra-wide parameter range.The proposed model leverages quantum superposition using Hadamard gates and quantum rotations along the X,Y,and Z axes to enhance randomness.Extensive numerical experiments validate the effectiveness of SQQLSR.The proposed method achieves a maximum Lyapunov exponent(LE)of≈55.265,surpassing traditional chaotic maps in unpredictability.The bifurcation analysis confirms a uniform chaotic distribution,eliminating periodic windows and ensuring higher randomness.The system also generates an expanded key space exceeding 10^(40),enhancing security against brute-force attacks.Additionally,SQQLSR is applied to image encryption using a simple three-layer encryption scheme combining permutation and substitution techniques.This approach is intentionally designed to highlight the impact of SQQLSR-generated chaotic sequences rather than relying on a complex encryption algorithm.Theencryption method achieves an average entropy of 7.9994,NPCR above 99.6%,and UACI within 32.8%–33.8%,confirming its strong randomness and sensitivity to minor modifications.The robustness tests against noise,cropping,and JPEG compression demonstrate its resistance to statistical and differential attacks.Additionally,the decryption process ensures perfect image reconstruction with an infinite PSNR value,proving the algorithm’s reliability.These results highlight SQQLSR’s potential as a lightweight yet highly secure encryption mechanism suitable for quantum cryptography and secure communications.
文摘InP quantum dots(QDs)have been a major building block of modern display technology due to their high photoluminescence quantum yield(PLQY)in the visible spectrum,superior stability,and eco-friendly composition.However,their applications at short-wave infrared(SWIR)have been hindered by their low efficiency.Here,we report the synthesis of efficient and SWIR-emitting InP QDs by precisely controlling the InP core nucleation using a low-cost ammonia phosphorus precursor,while avoiding size-limiting ZnCl_(2) for effective copper doping.Subsequent epitaxial growth of a lattice-matched ZnSe/ZnS multishell enhanced the QD sphericity and surface smoothness and yielded a record PLQY of 66% with an emission peak at 960 nm.When QDs were integrated as the high-refractive-index luminescent core of a liquid waveguide-based luminescent solar concentrator(LSC),the device achieved an optical efficiency of 7.36%.This performance arises from their high PLQY,spectral alignment with the responsivity peak of silicon solar cells,and the optimized core/cladding waveguide structure.These results highlight the potential of InP QDs as a promising nanomaterial for SWIR emission and applications.
基金supported by the Quantum Science and Technology-National Science and Technology Major Project (Grant No.2024ZD0302502 for WZ)the National Natural Science Foundation of China(Grant No.92365210 for WZ)+1 种基金Tsinghua Initiative Scientific Research Program (for WZ)the project of Tsinghua University-Zhuhai Huafa Industrial Share Company Joint Institute for Architecture Optoelectronic Technologies (JIAOT,for YH)。
文摘To fully utilize the resources provided by optical fiber networks,a cross-band quantum light source generating photon pairs,where one photon in a pair is at C band and the other is at O band,is proposed in this work.This source is based on spontaneous four-wave mixing(SFWM)in a piece of shallow-ridge silicon waveguide.Theoretical analysis shows that the waveguide dispersion could be tailored by adjusting the ridge width,enabling broadband photon pair generation by SFWM across C band and O band.The spontaneous Raman scattering(SpRS)in silicon waveguides is also investigated experimentally.It shows that there are two regions in the spectrum of generated photons from SpRS,which could be used to achieve cross-band photon pair generation.A chip of shallow-ridge silicon waveguide samples with different ridge widths has been fabricated,through which cross-band photon pair generation is demonstrated experimentally.The experimental results show that the source can be achieved using dispersion-optimized shallow-ridge silicon waveguides.This cross-band quantum light source provides a way to develop new fiber-based quantum communication functions utilizing both C band and O band and extends applications of quantum networks.
基金supported by the National Natural Science Foundation of China(Grant No.12465009)support from the Major Program of Jiangxi Provincial Natural Science Foundation,China(Grant No.20224ACB201007)。
文摘We propose a quantum Otto engine operating through a cycle of two isochoric processes,where the working substance interacts with a single-mode radiation field,and two unitary strokes,during which the working substance is decoupled from the field.We investigate the influence of quantum superposition and quantum internal friction on the engine's power output and efficiency,demonstrating that these quantum effects enhance both performance metrics.While these enhancements are accompanied by increased power fluctuations,we show that such fluctuations can be effectively mitigated through careful selection of control parameters.Our results reveal that the proposed quantum Otto engine can achieve performance regimes that are thermally inconceivable in classical systems,including surpassing the Otto efficiency limit and attaining 100%efficiency with nonzero power output.
文摘On May 9,2025 on the campus of the University of Science and Technology of China(USTC),Chinese Academy of Sciences(CAS),an exhibition was unveiled to celebrate the UN International Year of Quantum Science and Technology(IYQ)-a one-year-long worldwide event in memory of the founding of quantum mechanics(QM).
基金supported by the National Key Research and Development Program of China (Grant No.2022YFB2803100)the National Major Scientific Research Instrument Development Project(Grant No.22127901)+6 种基金the National Natural Science Foundation of China (Grant No.62305367)the Shanghai Natural Science Foundation (Grant No.25ZR1401379)the Natural Science Foundation of Zhejiang Province,China (Grant No.LZ24F050001)the Innovation Program for Quantum Science and Technology (Grant Nos.2021ZD0301500 and 2021ZD0303200)the National Natural Science Foundation of China (Grant Nos.T2325022,U23A2074,62061160487,and 62275240)the CAS Project for Young Scientists in Basic Research(Grant No.YSBR-049)the Fundamental Research Funds for the Central Universities。
文摘Quantum photonic integrated circuits offer enhanced stability and scalability for quantum communications,sensing, and computing. Transverse modes in multimode waveguides enable high-dimensional scalability and versatile photon manipulation, but practical adoption requires compact and fabrication-tolerant quantum interference devices. Here, we present an ultra-compact taper-stepped beamsplitter that enables quantum interference between photon pairs in different transverse modes, and cascade it to realize NOON state interferometry. We experimentally achieve high visibilities of 93.9% for HOM interference and 86.5% for NOON state interference,demonstrating that efficient mode interference with active tuning can be realized on this platform.
基金the support of the International Young Scientist Fellowship of the Institute of Physics,Chinese Academy of Sciences (Grant No.202407)supported by the Innovation Program for Quantum Science and Technology (Grant No.2024ZD0301700)+1 种基金the start-up grant at IOP-CAS.ZXL is supported by the Beijing Natural Science Foundation (Grant No.JR25007)the National Natural Science Foundation of China (Grants No.12347107and 12474146)。
文摘Entanglement asymmetry(EA) has emerged as a powerful tool for characterizing symmetry breaking in quantum many-body systems. In this Letter, we explore how symmetry is dynamically broken through the lens of EA in two distinct scenarios: a non-symmetric Hamiltonian quench and a non-symmetric random quantum circuit, with a particular focus on U(1) symmetry. In the former case, symmetry remains broken in the subsystem at late times, whereas in the latter case, the symmetry is initially broken and subsequently restored, consistent with the principles of quantum thermalization. Notably, the growth of EA exhibits unexpected overshooting behavior at early times in both contexts, contrasting with the behavior of charge variance. We also consider dynamics of non-symmetric initial states under the symmetry-breaking evolution. Due to the competition of symmetry-breaking in both the initial state and Hamiltonian, the early-time EA can increase and decrease, while quantum Mpemba effects remain evident despite the weak symmetry-breaking in both settings.
基金supported by the National Natural Science Foundation of China Grant Nos.12450004,12274288the Innovation Program for Quantum Science and Technology Grant No.2021ZD0301900。
文摘Quantum integrability provides a unique and powerful framework for accurately understanding quantum magnetism.In this review,we focus specifically on several quantum integrable low-dimensional quantum Ising models.We begin with the transverse field Ising chain(TFIC)at quantum critical point and examine how it evolves under perturbations,such as an applied longitudinal field or weak coupling to another quantum critical TFIC.
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 in part by the China Postdoctoral Science Foundation(Grant No.2023M740874)。
文摘The quantum hybrid algorithm has recently become a very promising and speedy method for solving larger-scale optimization problems in the noisy intermediate-scale quantum(NISQ)era.The unit commitment(UC)problem is a fundamental problem in the field of power systems that aims to satisfy the power balance constraint with minimal cost.In this paper,we focus on the implementation of the UC solution using exact quantum algorithms based on the quantum neural network(QNN).This method is tested with a ten-unit system under the power balance constraint.In order to improve computing precision and reduce network complexity,we propose a knowledge-based partially connected quantum neural network(PCQNN).The results show that exact solutions can be obtained by the improved algorithm and that the depth of the quantum circuit can be reduced simultaneously.
基金Gerhard Hellstern is partly funded by the Ministry of Economic Affairs,Labour and Tourism Baden-Württemberg in the frame of the Competence Center Quantum Computing Baden-Württemberg(QORA Ⅱ).
文摘The rapid advancement of quantum computing has sparked a considerable increase in research attention to quantum technologies.These advances span fundamental theoretical inquiries into quantum information and the exploration of diverse applications arising from this evolving quantum computing paradigm.The scope of the related research is notably diverse.This paper consolidates and presents quantum computing research related to the financial sector.The finance applications considered in this study include portfolio optimization,fraud detection,and Monte Carlo methods for derivative pricing and risk calculation.In addition,we provide a comprehensive analysis of quantum computing’s applications and effects on blockchain technologies,particularly in relation to cryptocurrencies,which are central to financial technology research.As discussed in this study,quantum computing applications in finance are based on fundamental quantum physics principles and key quantum algorithms.This review aims to bridge the research gap between quantum computing and finance.We adopt a two-fold methodology,involving an analysis of quantum algorithms,followed by a discussion of their applications in specific financial contexts.Our study is based on an extensive review of online academic databases,search tools,online journal repositories,and whitepapers from 1952 to 2023,including CiteSeerX,DBLP,Research-Gate,Semantic Scholar,and scientific conference publications.We present state-of-theart findings at the intersection of finance and quantum technology and highlight open research questions that will be valuable for industry practitioners and academicians as they shape future research agendas.
基金Project supported by the Open Fund of Anhui Key Laboratory of Mine Intelligent Equipment and Technology (Grant No. ZKSYS202204)the Talent Introduction Fund of Anhui University of Science and Technology (Grant No. 2021yjrc34)the Scientific Research Fund of Anhui Provincial Education Department (Grant No. KJ2020A0301)。
文摘Implementing quantum wireless multi-hop network communication is essential to improve the global quantum network system. In this paper, we employ eight-level GHZ states as quantum channels to realize multi-hop quantum communication, and utilize the logical relationship between the measurements of each node to derive the unitary operation performed by the end node. The hierarchical simultaneous entanglement switching(HSES) method is adopted, resulting in a significant reduction in the consumption of classical information compared to multi-hop quantum teleportation(QT)based on general simultaneous entanglement switching(SES). In addition, the proposed protocol is simulated on the IBM Quantum Experiment platform(IBM QE). Then, the data obtained from the experiment are analyzed using quantum state tomography, which verifies the protocol's good fidelity and accuracy. Finally, by calculating fidelity, we analyze the impact of four different types of noise(phase-damping, amplitude-damping, phase-flip and bit-flip) in this protocol.
文摘As quantum computing transitions from a theoretical domain to a practical technology, many aspects of established practice in software engineering are being faced with new challenges. Quantum Software Engineering has been developed to address the peculiar needs that arise with quantum systems’ dependable, scalable, and fault-tolerant software development. The present paper critically reviews how traditional software engineering methodologies can be reshaped to fit into the quantum field. This also entails providing some critical contributions: frameworks to integrate classical and quantum systems, new error mitigation techniques, and the development of quantum-specific testing and debugging tools. In this respect, best practices have been recommended to ensure that future quantum software can harness the evolving capabilities of quantum hardware with continued performance, reliability, and scalability. The work is supposed to act as a foundational guide for the researcher and developer as quantum computing approaches widespread scientific and industrial adoption.
文摘In this paper, classical and continuous variable (CV) quantum neural network hybrid multi-classifiers are presented using the MNIST dataset. Currently available classifiers can classify only up to two classes. The proposed architecture allows networks to classify classes up to n<sup>m</sup> classes, where n represents cutoff dimension and m the number of qumodes on photonic quantum computers. The combination of cutoff dimension and probability measurement method in the CV model allows a quantum circuit to produce output vectors of size n<sup>m</sup>. They are then interpreted as one-hot encoded labels, padded with n<sup>m</sup> - 10 zeros. The total of seven different classifiers is built using 2, 3, …, 6, and 8-qumodes on photonic quantum computing simulators, based on the binary classifier architecture proposed in “Continuous variable quantum neural networks” [1]. They are composed of a classical feed-forward neural network, a quantum data encoding circuit, and a CV quantum neural network circuit. On a truncated MNIST dataset of 600 samples, a 4-qumode hybrid classifier achieves 100% training accuracy.
文摘A team of researchers from the University of Science and Technology of China(USTC)of the Chinese Academy of Sciences(CAS)and its partners have made significant advancements in random quantum circuit sampling with Zuchongzhi-3,a superconducting quantum computing prototype featuring 105 qubits and 182 couplers.
文摘Quantum computing is a promising technology that has the potential to revolutionize many areas of science and technology,including communication.In this review,we discuss the current state of quantum computing in communication and its potential applications in various areas such as network optimization,signal processing,and machine learning for communication.First,the basic principle of quantum computing,quantum physics systems,and quantum algorithms are analyzed.Then,based on the classification of quantum algorithms,several important basic quantum algorithms,quantum optimization algorithms,and quantum machine learning algorithms are discussed in detail.Finally,the basic ideas and feasibility of introducing quantum algorithms into communications are emphatically analyzed,which provides a reference to address computational bottlenecks in communication networks.
文摘Background:Diabetic retinopathy remains one of the leading causes of vision impairment globally and poses diagnostic challenges due to the complexity of clinical imaging data and variability in disease progression.In this study,we propose an innovative methodology that integrates artificial intelligence and quantum computing to enhance the early detection and clinical management of diabetic retinopathy.Methods:We developed a hybrid model combining machine learning algorithms with simulated quantum circuits to classify retinal images and associated clinical data.Anonymized datasets were used,and deep inductive transfer techniques were applied to improve diagnostic precision and generalizability.Results:The proposed model achieved a classification accuracy of 94.6%,significantly reducing diagnostic time and improving the prioritization of high-risk cases compared to conventional methods.The hybrid approach demonstrated superior performance in processing speed and accuracy for complex clinical scenarios.Conclusion:This study highlights the potential of combining AI and quantum computing to revolutionize the diagnosis of diabetic retinopathy.The proposed model provides a scalable and efficient solution for clinical environments,enabling faster and more accurate decision-making in ophthalmic care.
