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Archimedean-Spiral-Based Microchip Ring Waveguide for Cold Atoms

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chinese Physics Letters 2015年第2期32卷 1-4页

作者：蒋小军李晓林许忻平张海潮王育竹 key laboratory for quantum Optics and Center for Cold Atom Physics of chinese academy of sciences Shanghai Institute of Optics and Fine MechanicsChinese Academy of Sciences University of chinese academy of sciences

We present a scheme for generating a ring magnetic waveguide on a single-layer atom chip. The wire layout consists of two interleaved Archimedean spirals of the same size. The waveguide avoids the trapping perturbation caused by the input and output ports, resulting in an enclosed guiding loop for neutral atoms in weak-field seeking states. Such a configuration can create a tight and deep trap potential with a small current. Taking the [F = 2, mF =2} state of 87Rb as an example, the trap frequency and depth are estimated to be 18kHz and 335 μK, respectively, with adc current of 2 A.

关键词： Archimedean-Spiral-Based Microchip Ring Waveguide for Cold Atoms

A Collaboration-Based Scheme for Location-Based Services with Incentive Mechanism

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chinese Journal of Electronics 2018年第2期27卷 310-317页

作者： WAN Sheng HUA Jiafeng ZHU Hui WANG Hanyi LI Fenghua State key laboratory of Integrated Services Networks Xidian University State key laboratory of information Security Institute of Information EngineeringChinese Academy of Sciences School of Cyber Security University of Chinese Academy of Sciences

With the proliferation of communication networks and mobile devices, Location-based services(LBSs) have brought a variety of applications and conveniences in our daily life. While LBSs greatly benefit users,they bring significant threats to users’ privacy. To enhance privacy protection for LBSs, a well-used technique is to establish a collaborative group which helps each other to avoid privacy leakage. Due to extremely unbalanced system overheads for group members, many users are short of intrinsic motivations to join the collaborative group in existing schemes. To address this problem, we propose a collaborative group system combined with dummy selection technique, termed CGS-DS, which not only limits mobile users consuming significant resources in collaborative group through the hop distance, but also inspires them to generate and cache the service data of dummies for other group members. Our CGS-DS uses a threshold assignment module to generate a suitable threshold of the hop distance. While the hop distance reaches the specified threshold, the user executes the dummy-cache module to generate some dummy queries and cache the service data for other members to use. Security analysis and evaluation results indicate its effectiveness and efficiency.

关键词： Location-based services(LBSs) Privacy protection Location privacy Collaborative group

Tomographic Approach in Reference-Frame-Independent Measurement-Device-Independent quantum key Distribution

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Communications in Theoretical Physics 2016年第11期65卷 496-500页

作者：方茜王超韩云光银振强陈巍韩正甫 key laboratory of quantum information Chinese Academy of Sciences University of Science and Technology of China Synergetic Innovation Center of quantum information & quantum Physics University of Science and Technology of China

Recently, a novel reference-frame-independent measurement-device-independent quantum key distribution protocol was proposed, which can remove all detector side channels as well as tolerate unknown and slow variance of reference frame without active alignment. In this paper, we propose a new tomographic method to estimate the key rate in that protocol. We estimate the key rate using conventional method and tomographic method respectively and compare the two methods by numerical simulation. The numerical simulation results show that tomographic approach is equivalent to the conventional approach, which can be used as an alternative method.

关键词： quantum key distribution tomographic reference-frame-independent measurement-deviceindependent

The DBlock family of block ciphers

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Science China(information sciences) 2015年第3期58卷 91-104页

作者： WU WenLing ZHANG Lei YU XiaoLi Trusted Computing and information Assurance laboratory Institute of SoftwareChinese Academy of Sciences State key laboratory of Computer Science Institute of Software Chinese Academy of Sciences

In this paper,we propose a new family of block ciphers named *** consists of three variants which are specified as DBlock-128,DBlock-192,and DBlock-256,***-n has the equal n-bit block length and key *** structure of DBlock successfully combines the advantages of Feistel and Type-2generalized Feistel structures ***,its design of round function employs different linear transforms operating on various word-sizes,which efficiently improve the diffusion *** key schedule of DBlock,it basically employs the same module used in encryption,except the choice of different byte permutations,which can improve its suitability for various implementation environments and also enhance its security against many cryptanalytic *** preliminary evaluation shows that DBlock can achieve enough security margin against known attacks,and it can also obtain excellent performances on various software and hardware platforms.

关键词： block cipher structure round function key scheduling security performance

Lattice-based PKEs/KEMs

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National Science Review 2021年第9期8卷 7-8页

作者： Xianhui Lu Jiang Zhang Institute of information Engineering Chinese Academy of Sciences State key laboratory of Cryptology

The invention of public-key cryptography(PKC) by Diffie and Hellman in 1976 is one of two milestones marking the beginning of modern cryptography. The security of a PKC system requires that it should be infeasible to compute the private key from a given public key, which in turn is typically guaranteed by the difficulty in solving some cryptographicfriendly mathematical problems. Among those problems, the integer factorization and discrete logarithm problems play pivotal roles in the development of public-key cryptography.

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An optical fiber spool for laser stabilization with reduced acceleration sensitivity to 10^(-12)/g

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chinese Physics B 2015年第10期24卷 256-261页

作者：胡永奇董靖黄军超李唐刘亮 key laboratory of quantum Optics and Center of Cold Atom Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of Sciences University of chinese academy of sciences

Environmental vibration causes mechanical deformation in optical fibers, which induces excess frequency noise in fiber-stabilized lasers. In order to solve such a problem, we propose an ultralow acceleration sensitivity fiber spool with symmetrically mounted structure. By numerical analysis with the finite element method, we obtain the optimal geometry parameters of the spool with which the horizontal and vertical acceleration sensitivity can be reduced to 3.25 × 10^-12/g and 5.38 × 10^-12/g respectively. Moreover, the structure features the insensitivity to the variation of geometry parameters,which will minimize the influence from numerical simulation error and manufacture tolerance.

关键词： laser stabilization optical fiber spool ultralow acceleration sensitivity optical fiber interferometer

Direct measurement and analysis of total ionizing dose effect on 130 nm PD SOI SRAM cell static noise margin

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chinese Physics B 2017年第9期26卷 335-340页

作者：郑齐文崔江维刘梦新苏丹丹周航马腾余学峰陆妩郭旗赵发展 key laboratory of Functional Materials and Devices for Special Environments Xinjiang Technical Institute of Physics and ChemistryChinese Academy of Sciences Xinjiang key laboratory of Electronic information Material and Device key laboratory of Silicon Device Technology Chinese Academy of Sciences University of chinese academy of sciences

In this work, the total ionizing dose（TID） effect on 130 nm partially depleted（PD） silicon-on-insulator（SOI） static random access memory（SRAM） cell stability is measured. The SRAM cell test structure allowing direct measurement of the static noise margin（SNM） is specifically designed and irradiated by gamma-ray. Both data sides＇ SNM of 130 nm PD SOI SRAM cell are decreased by TID, which is different from the conclusion obtained in old generation devices that one data side＇s SNM is decreased and the other data side＇s SNM is increased. Moreover, measurement of SNM under different supply voltages（Vdd） reveals that SNM is more sensitive to TID under lower Vdd. The impact of TID on SNM under data retention Vddshould be tested, because Vddof SRAM cell under data retention mode is lower than normal *** mechanism under the above results is analyzed by measurement of I–V characteristics of SRAM cell transistors.

关键词： silicon-on-insulator total ionizing dose static random access memory static noise margin

Effects of effective attractive multi-body interaction on quantum phase and transport dynamics of a strongly correlated bosonic gas across the superfluid to Mott insulator transition

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chinese Physics B 2013年第11期22卷 204-210页

作者：孙剑芳崔国栋姜伯楠钱军王育竹 key laboratory for quantum Optics Center for Cold Atom Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of Sciences University of chinese academy of sciences

We theoretically investigate quantum phases and transport dynamics of ultracold atoms trapped in an optical lattice in the presence of effective multi-body interaction. When a harmonic external potential is added, several interesting phenom- ena are revealed, such as the broadening and the emergence of a central insulator plateau and the phase transition between superftuid and Mott insulator phase. We also study the transport of the system which runs across the superfluid-insulator transition after ramping up the lattice, and predict a slower relaxation which is attributed to the influence of the multi-body interaction on the mass transport.

关键词： Bose-Hubbard model three-body interaction

Proposal of a dual-ball atomic fountain clock

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chinese Optics Letters 2011年第4期9卷 1-4页

作者：史春艳魏荣周子超李唐王育竹 key laboratory of quantum Optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of Sciences

A simple improved structure is designed to trap and launch two cold atomic balls vertically at the same time, which works like ＂two fountains＂, but is more compact since most components of the ＂two fountains＂ are ... 详细信息

关键词： Fountains