检索结果-南通市图书馆

Sensitivity of ghost imaging compared to conventional imaging [Invited]

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Optics Letters 2024年第6期22卷 15-32页

作者： Long-Kun Du Shuai Sun Yao-Kun Xu Hui-Zu Lin Ning-Yi Leng Wei-Tao Liu Institute for quantum Science and technology College of ScienceNational University of Defense TechnologyChangsha 410073China Interdisciplinary Center of quantum information National University of Defense TechnologyChangsha 410073China hunan key laboratory of mechanism and technology of quantum information Changsha 410073China College of Electronic Science and technology National University of Defense TechnologyChangsha 410073China Department of Mathematics College of ScienceNational University of Defense TechnologyChangsha 410073China

Ghost imaging has been attracting more and more attention, which provides a way to obtain images of objects with only a single-pixel detector. Considering possible applications, it becomes urgent to clarify the sensitivity of ghost imaging. Due to the unique characteristics of single-pixel detectors, which collect photons without distributing them to multiple pixels,often outperforming array sensors, ghost imaging is believed to be more sensitive than conventional imaging. However,a systematic analysis on the sensitivity of ghost imaging is yet to be completed. In this paper, we present a method for quantitatively assessing the sensitivity of ghost imaging. A detailed comparison is provided between ghost imaging and conventional imaging, taking into account the particle nature of photons and the noise of detection. With the settings of the two imaging methods being the same to the most extent, the minimal required number of detected photons for images of a certain quality is considered. For the thermal source version, ghost imaging demonstrates enhanced sensitivity under practical situations, with noise *** an entangled source, ghost imaging surpasses conventional imaging techniques in terms of sensitivity obviously. In one word, ghost imaging promises higher sensitivity at low photon flux and noisy situations.

关键词： sensitivity ghost imaging conventional imaging

quantum key distribution over a mimicked dynamic-scattering channel

在线全文

学校读者我要写书评

暂无评论

Science China(information Sciences) 2024年第4期67卷 323-330页

作者： Qi-Hang LU Fang-Xiang WANG Wei CHEN Hai-Yang FU Yin-Jie LU Shuang WANG De-Yong HE Zhen-Qiang YIN Guang-Can GUO Zheng-Fu HAN CAS key laboratory of quantum information University of Science and Technology of China CAS Center for Excellence in quantum information and quantum Physics University of Science and Technology of China Hefei National laboratory University of Science and Technology of China

Free-space quantum key distribution(QKD) plays an important role in the global quantum network. However, free space channels suffer from the atmospheric turbulence and scattering effects of haze,fog, and dust, which significantly weaken the performance of QKD or even block the secure quantum ***, we prove the performance of QKD over a dynamic scattering channel can be enhanced significantly using a fast wavefront shaping technique. The system achieves on average 10-dB enhancement of quantum transmission efficiency and establishes a secure quantum link for QKD. Our work demonstrates the feasibility of QKD through free-space dynamic scattering channels and enhances the deployment capability of complex-channel QKD system.

关键词： quantum key distribution free space channel channel turbulence channel scattering wavefront shaping

同方期刊数据库

Geometric phase helical PSF for simultaneous orientation and 3D localization microscopy

在线全文

学校读者我要写书评

暂无评论

Chinese Optics Letters 2024年第3期22卷 25-30页

作者：周勇壮张洪硕沈咏 Andrew R.Harvey 邹宏新 Institute for quantum Science and technology College of ScienceNational University of Defense TechnologyChangsha 410073China hunan key laboratory of mechanism and technology of quantum information Changsha 410073China School of Physics and Astronomy University of GlasgowGlasgow G128QQUK

The 3D location and dipole orientation of light emitters provide essential information in many biological,chemical,and physical *** acquisition of both information types typically requires pupil engineering for 3D localization and dual-channel polarization splitting for orientation *** we report a geometric phase helical point spread function for simultaneously estimating the 3D position and dipole orientation of point *** has a compact and simpler optical configuration compared to polarization-splitting techniques and yields achromatic phase modulation in contrast to pupil engineering based on dynamic phase,showing great potential for single-molecule orientation and localization microscopy.

关键词： PSF engineering geometric phase single-molecule orientation and localization microscopy

Parameter estimation in n-dimensional massless scalar field

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2024年第3期33卷 231-237页

作者：杨颖荆继良 hunan Provincial key laboratory of Intelligent Sensors and Advanced Sensor Materials School of Physics and ElectronicsHunan University of Science and TechnologyXiangtan 411201China Department of Physics Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Educationand Synergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal UniversityChangsha 410081Chin

quantum Fisher information(QFI)associated with local metrology has been used to parameter estimation in open quantum *** this work,we calculated the QFI for a moving Unruh-DeWitt detector coupled with massless scalar fields in n-dimensional spacetime,and analyzed the behavior of QFI with various parameters,such as the dimension of spacetime,evolution time,and Unruh *** discovered that the QFI of state parameter decreases monotonically from 1 to 0 over ***,we noted that the QFI for small evolution times is several orders of magnitude higher than the QFI for long evolution *** also found that the value of QFI decreases at first and then stabilizes as the Unruh temperature *** was observed that the QFI depends on initial state parameterθ,and Fθis the maximum forθ=0 orθ=π,Fφis the maximum forθ=π/*** also obtain that the maximum value of QFI for state parameters varies for different spacetime dimensions with the same evolution time.

关键词： quantum Fisher information parameter estimation open quantum systems

High-resolution recognition of FOAM modes via an improved EfficientNet V2 based convolutional neural network

在线全文

学校读者我要写书评

暂无评论

Frontiers of physics 2024年第3期19卷 175-183页

作者： Youzhi Shi Zuhai Ma Hongyu Chen Yougang Ke Yu Chen Xinxing Zhou International Collaborative laboratory of 2D Materials for Optoelectronics Science and technology Institute of Microscale OptoelectronicsShenzhen UniversityShenzhen 518060China key laboratory of Low-Dimensional quantum Structures and quantum Control of Ministry of Education Synergetic Innovation Center for Quantum Effects and ApplicationsSchool of Physics and ElectronicsHunan Normal UniversityChangsha 410081China key laboratory of hunan Province on information Photonics and Freespace Optical Communications School of Information Science and EngineeringHunan Institute of Science and TechnologyYueyang 414006China

Vortex beam with fractional orbital angular momentum (FOAM) is the excellent candidate for improving the capacity of free-space optical (FSO) communication system due to its infinite modes. Therefore, the recognition of FOAM modes with higher resolution is always of great concern. In this work, through an improved EfficientNetV2 based convolutional neural network (CNN), we experimentally achieve the implementation of the recognition of FOAM modes with a resolution as high as 0.001. To the best of our knowledge, it is the first time this high resolution has been achieved. Under the strong atmospheric turbulence (AT) (C_(n)^(2)=10^(-15)m^(-2/3)), the recognition accuracy of FOAM modes at 0.1 and 0.01 resolution with our model is up to 99.12% and 92.24% for a long transmission distance of 2000 m. Even for the resolution at 0.001, the recognition accuracy can still remain at 78.77%. This work provides an effective method for the recognition of FOAM modes, which may largely improve the channel capacity of the free-space optical communication.

关键词： OAM free-space optical communication deep learning convolutional neural network

Non-adiabatic holonomic quantum operations in continuous variable systems

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 12-19页

作者： Hao-Long Zhang Yi-Hao Kang Fan Wu Zhen-Biao Yang Shi-Biao Zheng Fujian key laboratory of quantum information and quantum Optics College of Physics and Information EngineeringFuzhou UniversityFuzhou 350116China

quantum operations by utilizing the underlying geometric phases produced in physical systems are favoured due to their potential *** a system in a non-degenerate eigenstate undergoes an adiabatically cyclic evolution dominated by its Hamiltonian,it will get a geometric phase,referred to as the Berry *** a non-adiabatically cyclic evolution produces an Aharonov-Anandan geometric *** two types of Abelian geometric phases are extended to the non-Abelian cases,where the phase factors become matrix-valued and the transformations associated with different loops are *** and non-Abelian(holonomic)operations are prevalent in discrete variable systems,whose limited(say,two)energy levels,form the *** their developments in continuous systems have also been investigated,mainly due to that,bosonic modes(in,such as,cat states)with large Hilbert spaces,provide potential advantages in fault-tolerant quantum *** we propose a feasible scheme to realize non-adiabatic holonomic quantum logic operations in continuous variable systems with cat *** construct arbitrary single-qubit(two-qubit)gates with the combination of single-and two-photon drivings applied to a Kerr Parametric Oscillator(KPO)(the coupled KPOs).Our scheme relaxes the requirements of the previously proposed quantum geometric operation strategies in continuous variable systems,providing an effective way for quantum control.

关键词： cat qubit continuous variable systems non-Abelian

同方期刊数据库

Measuring small longitudinal phase shifts via weak measurement amplification

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2024年第3期33卷 105-111页

作者：徐凯胡晓敏胡孟军王宁宁张超黄运锋柳必恒李传锋郭光灿张永生 CAS key laboratory of quantum information University of Science and Technology of ChinaHefei 230026China CAS Center For Excellence in quantum information and quantum Physics University of Science and Technology of ChinaHefei 230026China Hefei National laboratory University of Science and Technology of ChinaHefei 230088China Beijing Academy of quantum information Sciences Beijing 100193China

Weak measurement amplification,which is considered as a very promising scheme in precision measurement,has been applied to various small physical quantities *** many physical quantities can be converted into phase signals,it is interesting and important to consider measuring small longitudinal phase shifts by using weak ***,we propose and experimentally demonstrate a novel weak measurement amplification-based small longitudinal phase estimation,which is suitable for polarization *** realize one order of magnitude amplification measurement of a small phase signal directly introduced by a liquid crystal variable retarder and show that it is robust to the imperfection of ***,we analyze the effect of magnification error which is never considered in the previous works,and find the constraint on the *** results may find important applications in high-precision measurements,e.g.,gravitational wave detection.

关键词： weak measurement phase estimation quantum optics

Generation of visible Raman operation laser by a fiber electro-optical modulator feedback loop

在线全文

学校读者我要写书评

暂无评论

Chinese Optics Letters 2024年第2期22卷 180-185页

作者：李睿睿叶蔚然陈一龙陈树谦亓文昊崔金明黄运锋李传锋郭光灿 CAS key laboratory of quantum information University of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in quantum information and quantum Physics University of Science and Technology of ChinaHefei 230026China Hefei National laboratory University of Science and Technology of ChinaHefei 230088China

Phase-coherent multi-tone lasers play a critical role in atomic,molecular,and optical *** them,the Raman opeartion laser for manipulating atomic hyperfine qubits requires gigahertz bandwidth and low phase noise to retain long-term *** operation lasers generated by directly modulated and frequency-multipled infrared lasers are compact and stable but lack feedback control to actively suppress the phase noise,which limits their performance in practical *** this work,we employ a fiber electro-optical modulator driven by a voltage-controlled oscillator(VCO)to modulate a monochromatic laser and employ a second-harmonic generation process to convert it to the visible domain,where the beat note of the Raman operation laser is stabilized by controlling the output frequency of VCO with a digital phase-locked loop(PLL).The low-frequency phase noise is effectively suppressed compared to the scheme without active feedback and it reaches-80 d Bc/Hz@5 k Hz with a 20 k Hz loop ***,this compact and robust scheme effectively reduces the system's complexity and cost,which is promising for extensive application in atomic,molecular,and optical physics.

关键词： phase-coherent laser quantum information trapped ion stimulated Raman transition phase-locked loop

Stimulated Brillouin interaction between guided phonons and photons in a lithium niobate waveguide

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 173-175页

作者： Yuan-Hao Yang Jia-Qi Wang Zheng-Xu Zhu Xin-Biao Xu Qiang Zhang Juanjuan Lu Yu Zeng Chun-Hua Dong Luyan Sun Guang-Can Guo Chang-Ling Zou CAS key laboratory of quantum information University of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in quantum information and quantum Physics University of Science and Technology of ChinaHefei 230026China key laboratory of quantum Optics and quantum Optics Devices Institute of Opto-ElectronicsShanxi UniversityTaiyuan 030006China School of information Science and technology ShanghaiTech UniversityShanghai 201210China Center for quantum information Institute for Interdisciplinary Information SciencesTsinghua UniversityBeijing 100084China

The Brillouin scattering is one of the strongest nonlinear optical effects in dielectrics[1].In particular,the backward Brillouin scattering(BBS)provides an efficient method to achieve low-noise optical gain for active photonics[2]and the coherent interconnects between 10 GHz phonons and photons[3].However,previous studies on BBS are primarily limited to the unconfined phonons[1]or phonon confined in suspended structures[4-6].

关键词： scattering waveguide Brillouin