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
A quantum processor might execute certain computational tasks exponentially faster than a classical processor.Here,using superconducting quantum circuits we design a powerful universal quantum processor with the struc...A quantum processor might execute certain computational tasks exponentially faster than a classical processor.Here,using superconducting quantum circuits we design a powerful universal quantum processor with the structure of symmetric all-to-all capacitive connection.We present the Hamiltonian and use it to demonstrate a full set of qubit operations needed in the programmable universal quantum computations.With the device the unwanted crosstalk and ZZ-type couplings between qubits can be effectively suppressed by tuning gate voltages,and the design allows efficient and high-quality couplings of qubits.Within available technology,the scheme may enable a practical programmable universal quantum computer.展开更多
The historical significance of the Stern–Gerlach(SG)experiment lies in its provision of the initial evidence for space quantization.Over time,its sequential form has evolved into an elegant paradigm that effectively ...The historical significance of the Stern–Gerlach(SG)experiment lies in its provision of the initial evidence for space quantization.Over time,its sequential form has evolved into an elegant paradigm that effectively illustrates the fundamental principles of quantum theory.To date,the practical implementation of the sequential SG experiment has not been fully achieved.In this study,we demonstrate the capability of programmable quantum processors to simulate the sequential SG experiment.The specific parametric shallow quantum circuits,which are suitable for the limitations of current noisy quantum hardware,are given to replicate the functionality of SG devices with the ability to perform measurements in different directions.Surprisingly,it has been demonstrated that Wigner’s SG interferometer can be readily implemented in our sequential quantum circuit.With the utilization of the identical circuits,it is also feasible to implement Wheeler’s delayed-choice experiment.We propose the utilization of cross-shaped programmable quantum processors to showcase sequential experiments,and the simulation results demonstrate a strong alignment with theoretical predictions.With the rapid advancement of cloud-based quantum computing,such as BAQIS Quafu,it is our belief that the proposed solution is well-suited for deployment on the cloud,allowing for public accessibility.Our findings not only expand the potential applications of quantum computers,but also contribute to a deeper comprehension of the fundamental principles underlying quantum theory.展开更多
Quantum information processing platforms based on array of matter qubits,such as neutral atoms,trapped ions,and quantum dots,face significant challenges in scalable addressing and readout as system sizes increase.Here...Quantum information processing platforms based on array of matter qubits,such as neutral atoms,trapped ions,and quantum dots,face significant challenges in scalable addressing and readout as system sizes increase.Here,we propose the“Volcano”architecture that establishes a new quantum processing unit implementation method based on optical channel mapping on an arbitrarily arranged static qubit array.To support the feasibility of Volcano architecture,we show a proof-of-principle demonstration by employing a photonic chip that leverages custom-designed three-dimensional waveguide structures to transform one-dimensional beam arrays into arbitrary two-dimensional output patterns matching qubit array geometries.We demonstrate parallel and independent control of 49-channel system with negligible crosstalk and high uniformity.This architecture addresses the challenges in scaling up quantum processors,including both the classical link for parallel qubit control and the quantum link for efficient photon collection,and holds the potential for interfacing with neutral atom arrays and trapped ion crystals,as well as networking of heterogeneous quantum systems.展开更多
Using the principles of quantum state superposition and entanglement,quantum computing has been proven to be able to tackle problems that are hard for state-of-the-art supercomputers.Thirty years ago,when Shor’s algo...Using the principles of quantum state superposition and entanglement,quantum computing has been proven to be able to tackle problems that are hard for state-of-the-art supercomputers.Thirty years ago,when Shor’s algorithm and Grover’s algorithm were proposed and proven to have great acceleration on solving some problems,including factoring and searching,quantum computing was only a beautiful scientific dream.Today,quantum computing is advancing at an incredible pace.Over 10 years ago,Devoret and Schoelkopf said something similar in their review1.展开更多
We experimentally demonstrate a qubit-efficient variational quantum eigensolver(VQE)algorithm using a superconducting quantum processor,employing minimal quantum resources with only a transmon qubit coupled to a high-...We experimentally demonstrate a qubit-efficient variational quantum eigensolver(VQE)algorithm using a superconducting quantum processor,employing minimal quantum resources with only a transmon qubit coupled to a high-coherence photonic qubit.By leveraging matrix product states to compress the quantum state representation,we simulate an N+1-spin circular Ising model with a transverse field.Furthermore,we develop an analog error mitigation approach through zero-noise extrapolation by introducing a precise noise injection technique for the transmon qubit.As a validation,we apply our error-mitigated qubit-efficient VQE in determining the ground state energies of a 4-spin Ising model.Our results demonstrate the feasibility of performing quantum algorithms with minimal quantum resources while effectively mitigating the impact of noise,offering a promising pathway to bridge the gap between theoretical advances and practical implementations on current noisy intermediate-scale quantum devices.展开更多
We used deep learning techniques to construct various models for reconstructing quantum states from a given set of coincidence measurements.Through simulations,we have demonstrated that our approach generates function...We used deep learning techniques to construct various models for reconstructing quantum states from a given set of coincidence measurements.Through simulations,we have demonstrated that our approach generates functionally equivalent reconstructed states for a wide range of pure and mixed input states.Compared with traditional methods,our system offers the advantage of faster speed.Additionally,by training our system with measurement results containing simulated noise sources,the system shows a significant improvement in average fidelity compared with typical reconstruction methods.We also found that constraining the variational manifold to physical states,i.e.,positive semi-definite density matrices,greatly enhances the quality of the reconstructed states in the presence of experimental imperfections and noise.Finally,we validated the correctness and superiority of our model by using data generated on IBM Quantum Platform,a real quantum computer.展开更多
In this paper we report the optimal design and fabrication of a gold-on-silica linear segmented surface-electrode ion trap. By optimizing the thickness and width of the electrodes, we improved the trapping ability and...In this paper we report the optimal design and fabrication of a gold-on-silica linear segmented surface-electrode ion trap. By optimizing the thickness and width of the electrodes, we improved the trapping ability and trap scalability. By using some practical experimental operation methods, we successfully minimized the trap heating rate. Consequently, we could trap a string of up to 38 ions, and a zigzag structure with 24 ions, and transport two trapped ions to different zones. We also studied the influences of the ion chip surface on the ion lifetime. The excellent trapping ability and flexibility of operation of the planar ion trap shows that it has high feasibility for application in the development a practical quantum information processor or quantum simulator.展开更多
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A quantum processor might execute certain computational tasks exponentially faster than a classical processor.Here,using superconducting quantum circuits we design a powerful universal quantum processor with the structure of symmetric all-to-all capacitive connection.We present the Hamiltonian and use it to demonstrate a full set of qubit operations needed in the programmable universal quantum computations.With the device the unwanted crosstalk and ZZ-type couplings between qubits can be effectively suppressed by tuning gate voltages,and the design allows efficient and high-quality couplings of qubits.Within available technology,the scheme may enable a practical programmable universal quantum computer.
基金supported by Beijing Academy of Quantum Information Sciencessupported by the State Key Laboratory of Low Dimensional Quantum Physics+2 种基金the Start-up Fund provided by Tsinghua Universitythe financial support provided by the National Natural Science Foundation of China(Grant No.92065113)the Anhui Initiative in Quantum Information Technologies。
文摘The historical significance of the Stern–Gerlach(SG)experiment lies in its provision of the initial evidence for space quantization.Over time,its sequential form has evolved into an elegant paradigm that effectively illustrates the fundamental principles of quantum theory.To date,the practical implementation of the sequential SG experiment has not been fully achieved.In this study,we demonstrate the capability of programmable quantum processors to simulate the sequential SG experiment.The specific parametric shallow quantum circuits,which are suitable for the limitations of current noisy quantum hardware,are given to replicate the functionality of SG devices with the ability to perform measurements in different directions.Surprisingly,it has been demonstrated that Wigner’s SG interferometer can be readily implemented in our sequential quantum circuit.With the utilization of the identical circuits,it is also feasible to implement Wheeler’s delayed-choice experiment.We propose the utilization of cross-shaped programmable quantum processors to showcase sequential experiments,and the simulation results demonstrate a strong alignment with theoretical predictions.With the rapid advancement of cloud-based quantum computing,such as BAQIS Quafu,it is our belief that the proposed solution is well-suited for deployment on the cloud,allowing for public accessibility.Our findings not only expand the potential applications of quantum computers,but also contribute to a deeper comprehension of the fundamental principles underlying quantum theory.
基金supported by the National Key R&D Program of China (Grant No. 2021YFA1402004)the National Natural Science Foundation of China (Grant Nos. U21A20433, U21A6006, 92265210, and 92265108)+3 种基金Innovation Program for Quantum Science and Technology (Grant No. 2021ZD0300203)the Natural Science Foundation of Anhui Province (Grant No. 2408085QA017)supported by the Fundamental Research Funds for the Central UniversitiesUSTC Research Funds of the Double First-Class Initiative
文摘Quantum information processing platforms based on array of matter qubits,such as neutral atoms,trapped ions,and quantum dots,face significant challenges in scalable addressing and readout as system sizes increase.Here,we propose the“Volcano”architecture that establishes a new quantum processing unit implementation method based on optical channel mapping on an arbitrarily arranged static qubit array.To support the feasibility of Volcano architecture,we show a proof-of-principle demonstration by employing a photonic chip that leverages custom-designed three-dimensional waveguide structures to transform one-dimensional beam arrays into arbitrary two-dimensional output patterns matching qubit array geometries.We demonstrate parallel and independent control of 49-channel system with negligible crosstalk and high uniformity.This architecture addresses the challenges in scaling up quantum processors,including both the classical link for parallel qubit control and the quantum link for efficient photon collection,and holds the potential for interfacing with neutral atom arrays and trapped ion crystals,as well as networking of heterogeneous quantum systems.
文摘Using the principles of quantum state superposition and entanglement,quantum computing has been proven to be able to tackle problems that are hard for state-of-the-art supercomputers.Thirty years ago,when Shor’s algorithm and Grover’s algorithm were proposed and proven to have great acceleration on solving some problems,including factoring and searching,quantum computing was only a beautiful scientific dream.Today,quantum computing is advancing at an incredible pace.Over 10 years ago,Devoret and Schoelkopf said something similar in their review1.
基金supported by the National Natural Science Foundation of China(Grants Nos.11925404,92165209,92365301,92265210,11890704,92365206,12474498,T2225018,92270107,12188101,T2121001,and 62173201)the Innovation Program for Quantum Science and Technology(Grant Nos.2021ZD0300200,and 2021ZD0301800)+2 种基金the National Key R&D Program(Grants No.2017YFA0304303)supported by the Fundamental Research Funds for the Central UniversitiesUSTC Research Funds of the Double First-Class Initiative。
文摘We experimentally demonstrate a qubit-efficient variational quantum eigensolver(VQE)algorithm using a superconducting quantum processor,employing minimal quantum resources with only a transmon qubit coupled to a high-coherence photonic qubit.By leveraging matrix product states to compress the quantum state representation,we simulate an N+1-spin circular Ising model with a transverse field.Furthermore,we develop an analog error mitigation approach through zero-noise extrapolation by introducing a precise noise injection technique for the transmon qubit.As a validation,we apply our error-mitigated qubit-efficient VQE in determining the ground state energies of a 4-spin Ising model.Our results demonstrate the feasibility of performing quantum algorithms with minimal quantum resources while effectively mitigating the impact of noise,offering a promising pathway to bridge the gap between theoretical advances and practical implementations on current noisy intermediate-scale quantum devices.
文摘We used deep learning techniques to construct various models for reconstructing quantum states from a given set of coincidence measurements.Through simulations,we have demonstrated that our approach generates functionally equivalent reconstructed states for a wide range of pure and mixed input states.Compared with traditional methods,our system offers the advantage of faster speed.Additionally,by training our system with measurement results containing simulated noise sources,the system shows a significant improvement in average fidelity compared with typical reconstruction methods.We also found that constraining the variational manifold to physical states,i.e.,positive semi-definite density matrices,greatly enhances the quality of the reconstructed states in the presence of experimental imperfections and noise.Finally,we validated the correctness and superiority of our model by using data generated on IBM Quantum Platform,a real quantum computer.
基金supported by the National Basic Research Program of China(Grant No.2016YFA0301903)the National Natural Science Foundation of China(Grant Nos.11174370,11304387 and 61205108)the Research Plan Project of National University of Defense Technology(Grant No.ZK16-03-04)
文摘In this paper we report the optimal design and fabrication of a gold-on-silica linear segmented surface-electrode ion trap. By optimizing the thickness and width of the electrodes, we improved the trapping ability and trap scalability. By using some practical experimental operation methods, we successfully minimized the trap heating rate. Consequently, we could trap a string of up to 38 ions, and a zigzag structure with 24 ions, and transport two trapped ions to different zones. We also studied the influences of the ion chip surface on the ion lifetime. The excellent trapping ability and flexibility of operation of the planar ion trap shows that it has high feasibility for application in the development a practical quantum information processor or quantum simulator.
