题目：THz Resonances and Harmonic Generation by Hot Carriers in Graphene
报告人：Prof. J.P. Leburton（Department of Electrical and Computer Engineering,Beckman Institute, andDepartment of Physics, University of Illinois atUrbana-Champaign, Urbana, IL 61801）
摘要：
We discussed the onset of room temperature current oscillations induced by hot carriers interacting with high-energy optic phonons in graphene during the transient regime once the electric field is turned-on. We show that the oscillations only take place for a specific range of constant electric fields within a voltage and sample length window, and are the direct consequence of the interplay between the electric force and the randomizing nature of deformation potential optic phonons in the linear band structure of graphene. Within this range of parameters the effect manifests in damped terahertz oscillations of the carrier drift velocity and average energy [1].
When an oscillating (AC) electric field is superimposed to a DC field F, the current oscillations exhibit a soft resonance at the about half of the natural oscillation frequency of the carriers in the presence of the DC field [2]. This type of behavior is different from normal parametric resonance that would occur at . We also show that charge carrier transport exhibit different kind s of sharp resonances in the presence of spatially and temporarily modulated scattering, associated with the generation of higher harmonics characterized by large Q-factors, tunable with scattering periodicity.
[1]S. Sekwao and J.P. Leburton, Phys. Rev. B 83, 075418 (2011)
[2]S. Sekwao and J.P. Leburton, Phys. Rev. B 87, 155424 (2013)
简介：
Dr. Jean-Pierre Leburton is the G. Stillman Professor of Electrical and Computer Engineering at the University of Illinois in Urbana-Champaign. Dr. Leburton joined the University of Illinois in 1981 from Germany where he worked as a research scientist with the Siemens A.G. Research Laboratory in Munich. In 1992, he held the Hitachi LTD Chair on Quantum Materials at the University of Tokyo, and was a Visiting Professor in the Federal Polytechnic Institute in Lausanne, Switzerland in 2000. He is involved with research in nanostructures modeling and in quantum device simulation. His present research interest encompasses non-linear transport in quantum wires and carbon nanotubes.
Professor Leburton is author and co-author of more than 300 technical papers in international journals and books, and served in numerous conferences committees. In 1993 he was awarded the title of “Chevalier dansl’Ordre des PalmesAcademiques “ by the French Government. He is a Fellow of the Institute of Electrical and Electronic Engineers (IEEE), the American Physical Society (APS), the Optical Society of America (OSA), the American Association for the Advancement of Science (AAAS), the Electrochemical Society (ECS) and the Institute of Physics (IOP). He is also a member of the New York Academy of Science. In 2004 he was the recipient of the ISCS Quantum Device Award, and of the Gold medal for scientific achievement at the 75th anniversary of the Alumnus association of his Alma mater, the University of Liege, Belgium. He was a Distinguished Lecturer for the IEEE Nanotechnology Council for 2010-2013. In 2011 he was elected to Royal Academy of Sciences of Belgium.
时间：2014年10月27日下午14：00
地点：中科院物理研究所M236会议室
联系人：许秀来 研究员 （Tel：82649820）
金奎娟 研究员 （Tel：82648099）
主办单位：中国科学院光物理重点实验室
