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Preparation of cluster states with trapped electrons on a liquid helium surface

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Chinese Physics B 2011年第10期20卷 30-33页

作者：艾凌艳石艳丽张智明 College of Science Hebei United University Laboratory of Photonic Information Technology School of Information and Photoelectronic Science and Engineering South China Normal University

We present a scheme for the preparation of one-dimensional （1D） and two-dimensional （2D） cluster states with electrons trapped on a liquid helium surface and driven by a classical laser beam. The two lowest levels of the vertical motion of the electron act as a two-level system, and the quantized vibration of the electron along one of the parallel directions （the x direction） serves as the bosonic mode. The degrees of freedom of the vertical and parallel motions of the trapped electron can be coupled together by a classical laser field. With the proper frequency of the laser field, the cluster states can be realized.

关键词： cluster states electrons liquid helium

Study of hot electrons generated from intense laser-plasma interaction employing Image Plate

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Science China(Physics,Mechanics & Astronomy) 2008年第10期51卷 1455-1462页

作者： LIANG WenXi LI YuTong XU MiaoHua YUAN XiaoHui ZHENG ZhiYuan ZHANG Yi LIU Feng WANG ZhaoHua LI HanMing JIN Zhan WEI ZhiYi ZHAO Wei LI YingJun ZHANG Jie Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China State Key Laboratory of Transient Optics Technology Chinese Academy of SciencesXi’an 710068China School of Sciences China University of Mining and TechnologyBeijing 100083China

Image Plate (IP) is convenient to be used and very suitable for radiation detection because of its advantages such as wide dynamic range, high detective quantum efficiency, ultrahigh sensitivity and superior linearity. The function mechanism and characteristics of IP are introduced in this paper. IP was employed in the study of hot electrons generated from intense laser-plasma interaction. The angular distri- bution and energy spectrum of hot electrons were measured with IP in the experi- ments. The results demonstrate that IP is an effective radiation detector for the study of laser-plasma interaction.

关键词： IP laser-plasma interaction hot electrons

Discussion on the geometric factor in the detection of high energy electrons in geospace

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Science China(Technological Sciences) 2008年第1期51卷 1-9页

作者： CHEN HongFei SHI WeiHong ZOU Hong ZOU JiQing Institute of Space Physics and Applied Technology School of Earth and Space SciencesPeking UniversityBeijing 100871China

High energy electron is a kind of sources to be detected in the geospace environ- ment. Generally, the particle telescope with much thick semiconductor detector is used as the sensor for energetic electrons because they can penetrate deeply into the detector. The more energy of the electrons is, the deeper they can penetrate into, so that the geometric factor varies with energy of the incident electrons. We discuss the geometric factor of particle radiation detector (PRD), which is a payload on ZY-1 (CBERS-1 and CBERS-2) satellites to monitor the high energy particle ra- diation inside the satellites. According to the NASA’s AE8 model, the geometric factors of electrons for the low energy bin (0.5―1.0 MeV) and the high energy bin (> 2.0 MeV) are 2.468 and 1.736 cm2·sr, respectively. These results are much differ- ent from the traditional calculation of the geometric factor that is 1.18 cm2·sr. The angle-response function of the telescope is also derived, which can be useful for design of the telescope and analysis of the directional distribution.

关键词： geometric factor high energy electrons particle radiation space exploration

Latest progress on interactions between VLF/ELF waves and energetic electrons in the inner magnetosphere

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Science China Earth Sciences 2010年第3期53卷 317-326页

作者： XIAO FuLiang1,2, ZONG QiuGang3, SU ZhenPeng4, TIAN Tian3 & ZHENG HuiNan4 1 School of Physics and Electronic Sciences, Changsha University of Science and Technology, Changsha 410004, China 2 State Key Laboratory of Space Weather, Chinese Academy of Sciences, Beijing 100190, China 3 Institute of Space Physics and Applied Technology, Peking University, Beijing 100871, China 4 CAS Key Lab for Basic Plasma Science, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China School of Physics and Electronic Sciences Changsha University of Science and Technology Changsha China State Key Laboratory of Space Weather Chinese Academy of Sciences Beijing China Institute of Space Physics and Applied Technology Peking University Beijing China CAS Key Lab for Basic Plasma Science School of Earth and Space Sciences University of Science and Technology of China Hefei China

Interactions between very/extremely low frequency (VLF/ELF) waves and energetic electrons play a fundamental role in dynamics occurring in the inner magnetosphere. Here, we briefly discuss global properties of VLF/ELF waves, along with the variability of the electron radiation belts associated with wave-particle interactions and radial diffusion. We provide cases of electron loss and acceleration as a result of wave-particle interactions primarily due to such waves, and particularly some preliminary results of 3D evolution of phase space density from our currently developing 3D code. We comment on the existing mechanisms responsible for acceleration and loss, and identify several critical issues that need to be addressed. We review latest progress and suggest open questions for future investigation.

关键词： wave-particle interaction VLF/ELF waves energetic electrons acceleration and loss inner magnetosphere

Collimated quasi-monochromatic beams of accelerated electrons in the interaction of a weak-contrast intense femtosecond laser pulse with a metal foil

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High Power Laser Science and Engineering 2013年第2期1卷 80-87页

作者： Yu.A.Malkov A.N.Stepanov D.A.Yashunin L.P.Pugachev P.R.Levashov N.E.Andreev K.Yu.Platonov A.A.Andreev Institute of Applied Physics Russian Academy of Sciences ul. Ulyanova 46 603950 Nizhny Novgorod Russia Joint Institute of High Temperatures Russian Academy of Sciences Izhorskaya ul. 13 125412 Moscow Russia Federal State Unitary Enterprise ‘‘Scientific and Industrial Corporation ‘Vavilov State Optical Institute’’’ Birzhevay liniya 12 St 199034 Petersburg Russia

We demonstrated experimentally the formation of monoenergetic beams of accelerated electrons by focusing femtosecond laser radiation with an intensity of 2×1017W/cm2onto the edge of an aluminum foil.The electrons had energy distributions peaking in the 0.2–0.8 MeV range with energy spread less than 20%.The acceleration mechanism related to the generation of a plasma wave as a result of self-modulation instability of a laser pulse in a dense plasma formed by a prepulse(arriving 12 ns before the main pulse)is considered.One-dimensional and two-dimensional Particle in Cell(PIC)simulations of the laser–plasma interaction showed that effective excitation of a plasma wave as well as trapping and acceleration of an electron beam with an energy on the order of 1 MeV may occur in the presence of sharp gradients in plasma density and in the temporal shape of the pulse.

关键词： acceleration of electrons femtosecond laser radiation plasma wave self-modulation instability

Dynamic evolution of outer radiation belt electrons driven by superluminous R-X mode waves

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Science China(Technological Sciences) 2010年第10期53卷 2734-2738页

作者： XIAO FuLiang1,2, CHEN LiangXu1, HE YiHua1 & YANG Chang1 1 School of Physics and Electronic Sciences, Changsha University of Science and Technology, Changsha 410004, China 2 State Key Laboratory of Space Weather, Chinese Academy of Sciences, Beijing 100190, China School of Physics and Electronic Sciences Changsha University of Science and Technology Changsha China State Key Laboratory of Space Weather Chinese Academy of Sciences Beijing China

We present initial results on the temporal evolution of the phase space density (PSD) of the outer radiation belt energetic electrons driven by the superluminous R-X mode waves. We calculate diffusion rates in pitch angle and momentum assuming the standard Gaussian distributions in both wave frequency and wave normal angle at the location L=6.5. We solve a 2D momentum-pitch-angle Fokker-Planck equation using those diffusion rates as inputs. Numerical results show that R-X mode can produce significant acceleration of relativistic electrons around geostationary orbit,supporting previous findings that superluminous waves potentially contribute to dramatic variation in the outer radiation belt electron dynamics.

关键词： wave-particle interaction superluminous R-X waves phase space density evolution radiation belt electrons

A comparison of ionizing radiation damage in CMOS devices from ^(60)Co gamma rays,electrons and protons

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Chinese Physics C 2009年第6期33卷 436-439页

作者：何宝平姚志斌张凤祁 Northwest Institute of Nuclear Technology

Radiation hardened CC4007RH and non-radiation hardened CC4011 devices were irradiated using ^60Co gamma rays, 1 MeV electrons and 1-9 MeV protons to compare the ionizing radiation damage of the gamma rays with the charged particles. For all devices examined, with experimental uncertainty, the radiation induced threshold voltage shifts （△Vth） generated by ^60Co gamma rays are equal to that of 1 MeV electron and 1-7 MeV proton radiation under 0 gate bias condition. Under 5 V gate bias condition, the distinction of threshold voltage shifts （△Vth） generated by ^60Co gamma rays and 1 MeV electrons irradiation are not large, and the radiation damage for protons energy the proton has, the less serious below 9 MeV is always less than the radiation damage becomes. that of ^60Co gamma rays. The lower

关键词： gamma rays electrons protons radiation damage

In situ evidence of resonant interactions between energetic electrons and whistler waves in magnetopause reconnection

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Earth and Planetary Physics 2019年第6期3卷 467-473页

作者： Zhi Li QuanMing Lu RongSheng Wang XinLiang Gao HuaYue Chen Chinese Academy Sciences Key Laboratory of Geospace Environment Department of Geophysics and Planetary ScienceUniversity of Science and Technology of ChinaHefei 230026China Chinese Academy Sciences Center for Excellence in Comparative Planetology Hefei 230026China

In this paper,we analyze one reconnection event observed by the Magnetospheric Multiscale(MMS)mission at the earth’s magnetopause.In this event,the spacecraft crossed the reconnection current sheet from the magnetospheric side to the magnetosheath side,and whistler waves were observed on both the magnetospheric and magnetosheath sides.On the magnetospheric side,the whistler waves propagated quasi-parallel to the magnetic field and toward the X-line,while on the magnetosheath side they propagated almost anti-parallel to the magnetic field and away from the X-line.Associated with the enhancement of the whistler waves,we find that the fluxes of energetic electrons are concentrated around the pitch angle 90°when their energies are higher than the minimum energy that is necessary for the resonant interactions between the energetic electrons and whistler waves.This observation provides in situ observational evidence of resonant interactions between energetic electrons and whistler waves in the magnetic reconnection.

关键词： magnetic reconnection whistler waves magnetosphere energetic electrons

Uncovering the peculiar 4f electrons in heavy fermions

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Science China(Physics,Mechanics & Astronomy) 2021年第12期64卷 151-152页

作者： Yang Liu Center for Correlated Matter and Department of Physics Zhejiang UniversityHangzhou 310058China

Heavy fermion(HF) compounds are prototypical strongly correlated electron systems and are prime examples to study quantum critical phenomena. The f electrons, which form local moments at high temperatures, can acquire... 详细信息

关键词： quantum electrons conduction