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Improved impossible differential cryptanalysis of large-block Rijndael

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science China(Information sciences) 2019年第3期62卷 5-18页

作者： Ya LIU Yifan SHI Dawu GU Bo DAI Fengyu ZHAO Wei LI Zhiqiang LIU Zhiqiang ZENG Engineering Research Center of Optical instrument and System Ministry of Education Shanghai Key Lab of Modern Optical System University of Shanghai for Science and Technology State key laboratory of Cryptology Department of Computer science and Engineering Shanghai Jiao Tong University School of Computer science and Technology Donghua University Shanghai key laboratory of Scalable Computing and Systems Shanghai key laboratory of Integrated Administration Technologies for Information Security science and Technology on Information Assurance laboratory

Rijndael is a substitution-permutation network（SPN） block cipher for the AES development process. Its block and key sizes range from 128 to 256 bits in steps of 32 bits, which can be denoted by Rijndael-b-k, where b and k are the block and key sizes, respectively. Among them, Rijndael-128-128/192/256,that is, AES, has been studied by many researchers, and the security of other large-block versions of Rijndael has been exploited less frequently. However, more attention has been paid to large-block versions of block ciphers with the fast development of quantum computers. In this paper, we propose improved impossible differential attacks on 10-round Rijndael-256-256, 10-round Rijndael-224-256, and 9-round Rijndael-224-224 using precomputation tables, redundancies of key schedules, and multiple impossible differentials. For 10-round Rijndael-256-256, the data, time, and memory complexities of our attack were approximately 2;chosen plaintexts, 2;encryptions, and 2;blocks, respectively. For 10-round Rijndael-224-256, the data, time, and memory complexities of our attack were approximately 2;chosen plaintexts, 2;encryptions, and 2;blocks, respectively. For 9-round Rijndael-224-224, the data, time, and memory complexities of our attack are approximately 2;chosen plaintexts, 2;encryptions, and 2;blocks,respectively, or 2;chosen plaintexts, 2;encryptions, and 2;blocks, respectively. To the best of our knowledge, our results are currently the best on Rijndael-256-256 and Rijndael-224-224/256.

关键词： block cipher Rijndael precomputation tables impossible di?erentials multiple impossible differential attacks

Room-Temperature Processed Amorphous ZnRhCuO Thin Films with p-Type Transistor and Gas-Sensor Behaviors

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Chinese Physics Letters 2020年第9期37卷 108-111页

作者： Bojing Lu Rumin Liu Siqin Li Rongkai Lu Lingxiang Chen Zhizhen Ye Jianguo Lu State key laboratory of Silicon Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China key laboratory for Biomedical Engineering of Ministry of Education College of Biomedical Engineering and Instrument ScienceZhejiang UniversityHangzhou 310027China

We examine an amorphous oxide semiconductor(AOS)of *** a-ZnRhCuO films are deposited at room temperature,having a high amorphous quality with smooth surface,uniform thickness and evenly distributed elements,as well as a high visible transmittance above 87%with a wide bandgap of 3.12 *** a-ZnRhCuO films as active layers,thin-film transistors(TFTs)and gas sensors are *** TFT behaviors demonstrate the p-type nature of a-ZnRhCuO channel,with an on-to-off current ratio of^1×10^3 and field-effect mobility of0.079 cm^2 V^-1s^-*** behaviors of gas sensors also prove that the a-ZnRhCuO films are of p-type *** achievements relating to p-type a-ZnRhCuO films at room temperature with TFT devices may pave the way to practical applications of AOSs in transparent flexible electronics.

关键词： amorphous transparent films

Degradation behaviors of La–Mg–Ni-based metal hydride alloys:structural stability and influence on hydrogen storage performances

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Acta Metallurgica Sinica(English Letters) 2018年第9期31卷 897-909页

作者： Yi-Ming Li Bao-Yu Duan Zhuo-Cheng Liu Yang-Huan Zhang Hui-Ping Ren key laboratory of Integrated Exploitation of Bayan Obo Multi-Metal Resources Inner Mongolia University of Science and Technology Analytical and testing Center Inner Mongolia University of Science and Technology

The present work focuses on the structural stability upon hydrogenation of three typical La-Mg-Ni-based alloys： La2 MgNi9, LaaMgNi14 and La4MgNi19. Structural changes during gaseous and electrochemical cycles were characterized, and the influence of the structure distortion on the hydrogen storage properties was concerned. Hydrogen-induced amor- phization （HIA） and disproportionation of the three alloys have occurred during both the gaseous and electrochemical cycles. Structural stability of the phase structures in the La-Mg-Ni system is found to follow the order： LaNi5- 〉（La,Mg）5Ni19 〉（La,Mg）2Ni7 〉（La,Mg）Ni3 〉（La,Mg）Ni2. HIA increases thermal stability of the metal hydrides and difficulty to dehydrogenation and leads to degradation of both the gaseous and electrochemical capacities. Interestingly, LaEMgNi9 with poor stability presents elevated discharge capability even at 60 ℃ which can be attributed to increase in the hydrogen desorption capability and inhibition of the self-discharge induced by severe HIA at higher temperatures. In addition, HIA in the electrochemical reactions is obviously weaker than the extent during the gaseous cycles, which is mainly due to the slower hydrogenation speed. The development of HIA in the gaseous and electrochemical process is considered to follow the direct and gradual modes, respectively.

关键词： La-Mg-Ni-based alloys Degradation behaviors Hydrogen-induced amorphization Electrochemicalproperties

High-speed polarization mode dispersion measurement using digital polarization-state generators and Mueller matrix method

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Chinese Optics Letters 2010年第7期8卷 639-641页

作者：江俊峰刘铁根李茂春姚晓天刘琨 College of Precision instrument and Opto-Electronincs Engineering Tianjin UniversityKey Laboratory of Optoelectronics Information Technology and Science(Tianjin University)Ministry of Education

A polarization-mode dispersion （PMD） measurement system using a pair of polarization-state generators （PSGs） is demonstrated. Based on the saturation characteristics of magneto-optic rotators, the PSG can be digitally controlled, ensuring high-speed and highly repeatable generation of five distinct polarization states. Thus, the PSG can make full use of the advantage of the Mueller matrix method of PMD measurement. The experimental result shows that the system has good measurement repeatability and potential for field testing.

关键词： Dispersions

Spatial light modulation for femtosecond laser manufacturing:Current developments and challenges

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science China(Technological sciences) 2024年第1期67卷 60-72页

作者： ZANG Xue LIU ZiTing XU YiShi WANG Yi WANG Qing LI ZhenZe WANG Lei State key laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China State key laboratory of Precision Measurement and instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China

Since the invention of lasers,spatial-light-modulated laser processing has become a powerful tool for various *** enables multidimensional and dynamic modulation of the laser beam,which significantly improves the processing efficiency,accuracy,and flexibility,and presents wider prospects over traditional mechanical technologies for machining three-dimensional,hard,brittle,or transparent *** this review,we introduce:(1)The role of spatial light modulation technology in the development of femtosecond laser manufacturing;(2)the structured light generated by spatial light modulation and its generation methods;and(3)representative applications of spatial-light-modulated femtosecond laser manufacturing,including aberration correction,parallel processing,focal field engineering,and polarization ***,we summarize the present challenges in the field and possible future research.

关键词： femtosecond laser manufacturing spatial light modulation structured light aberration correction parallel processing focal field engineering polarization control

Analysis of terahertz waveguide modes in continuous wavelet domain

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Chinese Optics Letters 2010年第11期8卷 1057-1060页

作者：谷建强田震邢岐荣王昌雷栗岩锋刘丰柴路王清月 Center for Terahertz Waves and Ultrafast Laser laboratory College of Precision Instrument and Optoelectronics EngineeringKey Laboratory of Opto-Electronics Information and Technical Science (Ministry of Education)Tianjin University

Conventional analytical methods in the wavelet domain are used to present an analysis of terahertz （THz） waveguide *** obtain THz radiation pulses passing through a waveguide,we build a simple experimental system with a 5-mm-long,230-μm-inner-diameter stainless steel *** single-mode guided signal from the experiments and the multi-mode signal of a similar THz waveguide reported in the literature are analyzed using the continuous wavelet transform （CWT）.The results demonstrate that analyzing THz waveguide modes in the wavelet domain not only possesses all the functionality of the traditional THz time-domain spectroscopy （TDS） data processing but also has the ability to unscramble quantitatively and intuitively detailed information about the target samples,such as mode type,cut-off frequency,amplitude distinction,and group velocity.

关键词： Data handling Stainless steel Terahertz waves Time domain analysis Waveguides Wavelet transforms

Superconducting nanowire single-photon detectors:recent progress

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science Bulletin 2015年第23期60卷 1980-1983页

作者： Xiaolong Hu Yuhao Cheng Chao Gu Xiaotian Zhu Haiyi Liu School of Precision instrument and Optoelectronic Engineering Tianjin University key laboratory of Opto-electronic Information science and Technology Ministry of Education

Research of superconducting nanowire singlephoton detectors(SNSPDs) has been progressing rapidly in recent years. The combined properties of high efficiency,low noise, and fast speed of SNSPDs permit its applications ranging from long-distance quantum teleportation to moonto-earth optical communications. Here we briefly discussed recent progress of SNSPDs, in particular(1) tungstensilicide SNSPDs,(2) waveguide-integrated SNSPDs, and(3) a few applied demonstrations.

关键词： Superconducting nanowire single-photon detectors · Quantum optics · Nanowire·Superconducting devices

Numerical analysis of multicore photonic crystal fibers

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Chinese Optics Letters 2003年第10期1卷 570-572页

作者：栗岩锋王清月胡明列 key laboratory of Optoelectronic Information Technical science EMC Ultrafast Laser laboratory College of Precision Instrument and Optoelectronics Engineering Tianjin University Tianjin 300072

A Galerkin's method-based numerical procedure is extended to obtain the modal field distribution of multicore photonic crystal fibers for the first time to our knowledge, which can reveal how the air hole size influences the mode coupling and how the coupling strength varies with wavelength. These results will be helpful in the future design of multicore photonic crystal fibers with proper guidance properties.

关键词： Optical communication Optical fiber coupling Optical sensors

Terahertz flexible multiplexing chip enabled by synthetic topological phase transitions

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National science Review 2024年第08期11卷 157-166页

作者： Hang Ren Su Xu Zhidong Lyu Yuanzhen Li Zuomin Yang Quan Xu Yong-Sen Yu Yanfeng Li Fei Gao Xianbin Yu Jiaguang Han Qi-Dai Chen Hong-Bo Sun State key laboratory of Integrated Optoelectronics College of Electronic Science and Engineering Jilin University College of Information science and Electronic Engineering Zhejiang University Center for Terahertz Waves and College of Precision instrument and Optoelectronics Engineering Key Laboratory of Optoelectronic Information Technology(Ministry of Education of China) Tianjin University Guangxi key laboratory of Optoelectronic Information Processing School of Optoelectronic Engineering Guilin University of Electronic Technology State key laboratory of Precision Measurement Technology and instruments Department of Precision InstrumentTsinghua University

Flexible multiplexing chips that permit reconfigurable multidimensional channel utilization are indispensable for revolutionary 6G terahertz communications,but the insufficient manipulation capability of terahertz waves prevents their practical ***,we propose the first experimental demonstration of a flexible multiplexing chip for terahertz communication by revealing the unique mechanism of topological phase(TP) transition and perseveration in a heterogeneously coupled bilayer valley Hall topological photonic *** synthetic and individual TPs operated in the coupled and decoupled states enable controllable on-chip modular TP transitions and subchannel *** time-frequency interleaved subchannels support 10-and 12-Gbit/s QAM-16 high-speed data streams along corresponding paths over carriers of 120 and 130 GHz with 2.5-and 3-GHz bandwidths,*** work unlocks interlayer heterogeneous TPs for inspiring ingenious on-chip terahertz-wave regulation,allowing functionality-reconfigurable,compactly integrated and CMOS-compatible chips.

关键词： terahertz technology topological phase transitions flexible multiplexing 6G communications silicon chips