检索结果-内蒙古大学图书馆

Conference on Lasers and Electro-Optics (CLEO)

作者： Mamoru Endo Ruofan He Tatsuki Sonoyama Kazuma Takahashi Takahiro Kashiwazaki Takeshi Umeki Sachiko Takasu Kaori Hattori Daiji Fukuda Kosuke Fukui Kan Takase Warit Asavanant Jun-Ichi Yoshikawa Akira Furusawa Department of Applied Physics School of Engineering The University of Tokyo Bunkyo Tokyo Japan Optical Quantum Computing Research Team RIKEN Center for Quantum Computing Wako Saitama Japan NTT Device Technology Labs. NTT Corporation Atsugi Kanagawa Japan National Institute of Advanced Industrial Science and Technology Tsukuba Ibaraki Japan AIST-UTokyo Advanced Operando-Measurement Technology Open Innovation Laboratory Tsukuba Ibaraki Japan

Non-Gaussian quantum states were generated by photon subtraction of up to four photons from a squeezed light at 1545.32 nm. The Wigner negativity and the parity change with the subtracted photon number were directly o... 详细信息

ISBN: (纸本)9781957171258

关键词： Bandpass filters Light wavelength Photons Pulsed operation quantum information processing Squeezed states

来源：评论

学校读者我要写书评

暂无评论

Embedding All Feasible Solutions of Traveling Salesman Problem by Divide-and-Conquer quantum Search

Embedding All Feasible Solutions of Traveling Salesman Probl...

引用

quantum computing and engineering (QCE), IEEE International Conference on

作者： Rei Sato Kazuhiro Saito Tetsuro Nikuni Shohei Watabe Quantum Computing Project KDDI Reserch Inc. Fujimino Saitama Japan Department of Physics Faculty of Science Division I Tokyo University of Science Tokyo Japan Faculty of Engineering Computer Science and Engineering Shibaura Institute of Technology Tokyo Japan

quantum search algorithms, such as the Grover algorithm, are investigated as one of the ways to solve a traveling salesman problem (TSP). In TSP, the quantum search starts from an equal superposition of all feasible solutions. The embedding cost of all feasible solutions is up to exponential, i.e., $\mathcal{O}(n!)$ with $n$ cities, and makes it difficult to solve large-scale TSP. Hence, preparing the initial state of TSP at a lower embedding cost is an important issue. Here, we propose a quantum search algorithm based on the divide-and-conquer approach, which divides each constraint term of the TSP into subproblems and applies the quantum search to each subproblem. We investigate the embedding quality of all feasible solutions by comparing our proposed method with the Grover algorithm regarding optimal iterations and success probability. The results show that our quantum divide-and-conquer approach can significantly reduce the embedding cost while the success probability decreases.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Deep-Neural-Network Discrimination of Multiplexed Superconducting-Qubit States

引用

Physical Review Applied 2022年第1期17卷 014024-014024页

作者： Benjamin Lienhard Antti Vepsäläinen Luke C.G. Govia Cole R. Hoffer Jack Y. Qiu Diego Ristè Matthew Ware David Kim Roni Winik Alexander Melville Bethany Niedzielski Jonilyn Yoder Guilhem J. Ribeill Thomas A. Ohki Hari K. Krovi Terry P. Orlando Simon Gustavsson William D. Oliver Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology Cambridge Massachusetts 02139 USA Research Laboratory of Electronics Massachusetts Institute of Technology Cambridge Massachusetts 02139 USA Quantum Engineering and Computing Group Raytheon BBN Technologies Cambridge Massachusetts 02138 USA MIT Lincoln Laboratory Lexington Massachusetts 02421 USA

Demonstrating a quantum computational advantage will require high-fidelity control and readout of multiqubit systems. As system size increases, multiplexed qubit readout becomes a practical necessity to limit the growth of resource overhead. Many contemporary qubit-state discriminators presume single-qubit operating conditions or require considerable computational effort, limiting their potential extensibility. Here, we present multiqubit readout using neural networks as state discriminators. We compare our approach to contemporary methods employed on a quantum device with five superconducting qubits and frequency-multiplexed readout. We find that fully connected feedforward neural networks increase the qubit-state-assignment fidelity for our system. Relative to contemporary discriminators, the assignment error rate is reduced by up to 25% due to the compensation of system-dependent nonidealities such as readout crosstalk, which is reduced by up to one order of magnitude. Our work demonstrates a potentially extensible building block for high-fidelity readout relevant to both near-term devices and future fault-tolerant systems.

关键词： Machine learning Measurement-based quantum computing Optoelectronics quantum control quantum information with solid state qubits Superconducting qubits Artificial neural networks Microwave techniques

来源：评论

学校读者我要写书评

暂无评论

Visualizing nonlinear resonance in nanomechanical systems via single-electron tunneling

引用

Nano Research 2021年第4期14卷 1156-1161页

作者： Xinhe Wang Lin Cong Dong Zhu Zi Yuan Xiaoyang Lin Weisheng Zhao Zaiqiao Bai Wenjie Liang Ximing Sun Guang-Wei Deng Kaili Jiang Fert Beijing Research Institute School of Microelectronics&Beijing Advanced Innovation Centre for Big Data and Brain Computing(BDBC)Beihang UniversityBeijing 100191China State Key Laboratory of Low-Dimensional Quantum Physics Department of Physics and Tsinghua-Foxconn Nanotechnology Research CenterTsinghua UniversityBeijing 100084China Key Laboratory of Quantum Information CASUniversity of Science and Technology of ChinaHefei 230026China Department of Physics Beijing Normal UniversityBeijing 100875China Institute of Physics Chinese Academy of SciencesBeijing 100080China Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy TechnologyKey Laboratory of Advanced Reactor EngineeringTsinghua UniversityBeijing 100084China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China

Numerous reports have elucidated the importance of mechanical resonators comprising quantum-dot-embedded carbon nanotubes(CNTs)for studying the effects of single-electron ***,there is a need to investigate the single-electron transport that drives a large amplitude into a nonlinear ***,a CNT hybrid device has been investigated,which comprises a gate-defined quantum dot that is embedded into a mechanical resonator under strong actuation *** Coulomb peak positions synchronously oscillate with the mechanical vibrations,enabling a single-electron Chopper*1 ***,the vibration amplitude of the CNT versus its frequency can be directly visualized via detecting the time-averaged single-electron tunneling *** understand this phenomenon,a general formula is derived for this time-averaged single-electron tunneling current,which agrees well with the experimental *** using this visualization method,a variety of nonlinear motions of a CNT mechanical oscillator have been directly recorded,such as Duffing nonlinearity,parametric resonance,and double-,fractional-,mixed-frequency *** approach opens up burgeoning opportunities for investigating and understanding the nonlinear motion of a nanomechanical system and its interactions with electron transport in quantum regimes.

关键词： carbon nanotube mechanical resonator quantum dot nonlinear coupling

来源：评论

学校读者我要写书评

暂无评论

Free-space Continuous-variable quantum Secret Sharing

arXiv

引用

arXiv 2025年

作者： Yang, Fangli Chang, Liang Qiu, Daowen Pan, Minghua Xiong, Wanjun Guangxi Key Laboratory of Trusted Software Guilin University of Electronic Technology Guilin541004 China Institute of Quantum Computing and Software School of Computer Science and Engineering Sun Yat-sen University Guangzhou510006 China Guangxi Key Laboratory of Cryptography and Information Security Guilin University of Electronic Technology Guilin541004 China

Free-space quantum cryptography has the potential to enable global quantum communication. However, most existing continuous-variable quantum secret sharing (CV-QSS) schemes rely on fiber channels. In this paper, we present a CV-QSS protocol designed for free-space transmission and construct models of crucial parameters, including channel transmittance, excess noise, and interruption probability, thus deriving the bound of the secret key rate. In particular, we provide a multi-source excess noise model for free-space CV-QSS based on the local local oscillator (LLO) scheme and a straightforward optimization of the noise. Furthermore, our research considers the impact of atmospheric turbulence on the protocol. Simulation results demonstrate that the intensification of atmospheric turbulence adversely affects the aforementioned crucial parameters, leading to a significant reduction in the key rate. However, our protocol shows its capability to securely share secrets over a distance of exceeding 60 km among five participants in the presence of turbulence with Cn2 = 1 × 10−15m−2/3, while maintaining a high key rate of approximately 0.55 bit/pulse over a distance of 10 km across twenty participants. These findings suggest that efficient CV-QSS in free space is indeed achievable. This research may serve as a reference for the design and optimization of the practical CV-QSS system. Copyright © 2025, The Authors. All rights reserved.

关键词： Atmospheric turbulence

来源：评论

学校读者我要写书评

暂无评论

Review: quantum Metrology and Sensing with Many-Body Systems

arXiv

引用

arXiv 2024年

作者： Montenegro, Victor Mukhopadhyay, Chiranjib Yousefjani, Rozhin Sarkar, Saubhik Mishra, Utkarsh Paris, Matteo G.A. Bayat, Abolfazl Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of China Chengdu611731 China Key Laboratory of Quantum Physics and Photonic Quantum Information Ministry of Education University of Electronic Science and Technology of China Chengdu611731 China Qatar Center for Quantum Computing College of Science and Engineering Hamad Bin Khalifa University Doha Qatar Department Of Physics and Astrophysics University of Delhi Delhi110007 India Universita di Milano MilanoI-20133 Italy

quantum systems, fabricated across various spatial scales from nano to micrometers, are very delicate and naturally sensitive to the variations of their environment. These features make them excellent candidates for serving as sensors with wide range of applications. The size versatility as well as their sensitivity, allow quantum sensors to achieve unprecedented precision with ultra-high spatial resolution. The main power of quantum sensors is achieved when the probe is composed of several particles. In this situation, quantum features such as entanglement contribute in enhancing the precision of quantum sensors beyond the capacity of classical sensors, a phenomenon that is referred to as quantum enhanced sensitivity. Originally, quantum sensing was formulated for non-interacting particles which are prepared in a special form of maximally entangled states. These probes are extremely sensitive to decoherence and any interaction between particles is detrimental to their performance. An alternative framework for quantum sensing has been developed exploiting quantum many-body systems, where the interaction between particles plays a crucial role. In this review, we investigate different aspects of the latter approach for quantum metrology and sensing. Many-body probes have been used for sensing purposes in both equilibrium and non-equilibrium scenarios. quantum criticality has been identified as a resource for achieving quantum enhanced sensitivity in both of these scenarios. In equilibrium, various types of criticalities, such as first order, second order, topological, and localization phase transitions have been exploited for sensing purposes. In nonequilibrium scenarios, quantum enhanced sensitivity has been discovered for Floquet, dissipative, and time crystal phase transitions. While each type of these criticalities, either in equilibrium or nonequilibrium scenarios, has its own characteristics, the presence of one feature is crucial for achieving quantum enhanced

关键词： quantum entanglement

来源：评论

学校读者我要写书评

暂无评论

Strain-tunable magnetic compensation temperature of epitaxial Tb3Fe5O12 thin films

引用

Physical Review B 2023年第18期108卷 184403-184403页

作者： Yufei Li Xihui Yang Hua Bai Mingzhi Wang Dashuai Cheng Cheng Song Zhe Yuan Yi Liu Zhong Shi Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology and Pohl Institute of Solid State Physics and School of Physics Science and Engineering Tongji University Shanghai 200092 China Center for Advanced Quantum Studies and Department of Physics Beijing Normal University Beijing 100875 China Key Laboratory of Advanced Materials School of Materials Science and Engineering Beijing Innovation Center for Future Chips Tsinghua University Beijing 100084 China Institute for Nanoelectronic Devices and Quantum Computing Fudan University Shanghai 200433 China

High-quality rare-earth iron garnet (ReIG) Tb3Fe5O12 (TbIG) thin films are epitaxially grown on a series of (111)-oriented garnet substrates with various lattice constants. The coherent growth induces a substrate-dependent in-plane tensile or compressive strain in the TbIG film. Measurements of the anomalous Hall-like effect in TbIG/Pt heterostructures show that the compensation temperature of TbIG films monotonically changes with the film strain. The strain results in a variation of the distances between magnetic atoms in the TbIG crystal and therefore the corresponding exchange interactions. The latter is explicitly calculated as a function of the lattice strain based on density-functional theory, reproducing the observed experimental results. This work provides a versatile way to optimize ReIG-based spin-orbit torque devices.

关键词： Anomalous Hall effect Epitaxial strain Exchange interaction Ferrimagnetism Magnetoelastic effect

来源：评论

学校读者我要写书评

暂无评论

Coherent Detection of the Oscillating Acoustoelectric Effect in Graphene

引用

Physical Review Letters 2025年第9期134卷 096301-096301页

作者： Yicheng Mou Jiayu Wang Haonan Chen Yingchao Xia Hailong Li Qing Yan Xue Jiang Yijia Wu Wu Shi State Key Laboratory of Surface Physics and Institute for Nanoelectronic Devices and Quantum Computing Fudan University Shanghai 200433 China International Center for Quantum Materials School of Physics Peking University Beijing 100871 China Interdisciplinary Center for Theoretical Physics and Information Sciences (ICTPIS) Fudan University Shanghai 200433 China Department of Biomedical Engineering School of Information Science and Technology Fudan University Shanghai 200433 China Zhangjiang Fudan International Innovation Center Fudan University Shanghai 201210 China

In recent years, surface acoustic waves (SAWs) have emerged as a novel technique for generating quasiparticle transport and band modulation in condensed matter systems. SAWs interact with adjacent materials through piezoelectric and strain fields, dragging carriers in the direction of wave propagation. Most studies on the acoustoelectric effect have focused on the collective directional motion of carriers, which generates a steady electric potential difference, while the oscillating component from dynamic spatial charge modulation has remained challenging to probe. In this Letter, we report the coherent detection of the oscillating acoustoelectric effect in graphene. This is achieved through the coherent rectification of spatial-temporal charge oscillation with electromagnetic waves emitted by interdigital transducers. We systematically investigate the frequency and gate dependence of rectified signals and quantitatively probe the carrier redistribution dynamics driven by SAWs. The observation of the oscillating acoustoelectric effect provides direct access to the dynamic spatial charge modulation induced by SAWs through transport experiments.

关键词： Acoustoelectric effects

来源：评论

学校读者我要写书评

暂无评论

Stacking of charge-density waves in 2H−NbSe2 bilayers

引用

Physical Review Research 2024年第4期6卷 043111页

作者： F. Cossu D. Nafday K. Palotás M. Biderang H.-S. Kim A. Akbari I. Di Marco Department of Physics and Institute of Quantum Convergence and Technology – Pohang Gyeongbuk 37673 Korea Department of Physics School of Natural and Computing Sciences School of Physics Engineering and Technology Department of Applied Physics School of Engineering Sciences Institute for Solid State Physics and Optics HUN-REN-SZTE Reaction Kinetics and Surface Chemistry Research Group Department of Physics Beijing Institute of Mathematical Sciences and Applications (BIMSA) Huairou District Beijing 101408 China Institut für Theoretische Physik III Department of Physics and Astronomy Institute of Physics

We employ ab initio electronic-structure calculations to investigate the charge-density waves and periodic lattice distortions in bilayer 2H−NbSe2. We demonstrate that the vertical stacking can give rise to a variety of patterns that may lower the symmetry of the charge-density waves exhibited separately by the two composing 1H−NbSe2 monolayers. The general tendency to a spontaneous symmetry breaking observed in the ground state and the first excited states is shown to originate from a non-negligible interlayer coupling. Simulated images for scanning tunneling microscopy as well as geometric structure factors show signatures of the different stacking orders. This may not only be useful to reinterpret past experiments on surfaces and thin films, but it may also be exploited to devise ad hoc experiments for the investigation of the stacking order in 2H−NbSe2. We anticipate that our analysis not only applies to the 2H−NbSe2, but is also relevant for thin films and bulk, whose smallest centrosymmetric component is indeed the bilayer. Finally, our results illustrate clearly that the vertical stacking is not only important for 1T structures, as exemplified by the metal-to-insulator transition observed in 1T−TaS2, but seems to be a general feature of metallic layered transition metal dichalcogenides as well.

关键词： Charge density waves Chemical bonding First-principles calculations Peierls transition Bilayer films Electronic structure Transition metal dichalcogenides Density functional theory

来源：评论

学校读者我要写书评

暂无评论

Efficient quantum Circuits for Machine Learning Activation Functions including Constant T-depth ReLU

arXiv

引用

arXiv 2024年

作者： Zi, Wei Wang, Siyi Kim, Hyunji Sun, Xiaoming Chattopadhyay, Anupam Rebentrost, Patrick State Key Lab of Processors Institute of Computing Technology Chinese Academy of Sciences Beijing China School of Computer Science and Technology University of Chinese Academy of Sciences Beijing China School of Computer Science and Engineering Nanyang Technological University Singapore Hansung University Seoul Korea Republic of Centre for Quantum Technologies National University of Singapore Singapore School of Computing National University of Singapore Singapore

In recent years, quantum Machine Learning (QML) has increasingly captured the interest of researchers. Among the components in this domain, activation functions hold a fundamental and indispensable role. Our research focuses on the development of activation functions quantum circuits for integration into fault-tolerant quantum computing architectures, with an emphasis on minimizing T-depth. Specifically, we present novel implementations of ReLU and leaky ReLU activation functions, achieving constant T-depths of 4 and 8, respectively. Leveraging quantum lookup tables, we extend our exploration to other activation functions such as the sigmoid. This approach enables us to customize precision and T-depth by adjusting the number of qubits, making our results more adaptable to various application scenarios. This study represents a significant advancement towards enhancing the practicality and application of quantum machine learning. Copyright © 2024, The Authors. All rights reserved.

关键词： Table lookup

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：