讲座题目一:Surface State Electrons on liquid helium surface
演讲人:Kimitoshi Kono 教授
Team Leader, Quantum Condensed Phases Research, RIKEN CEMS
Electrons slowly approaching from outside to liquid helium surface cannot enter liquid He because of large negative electron affinity of He atoms. Rather, they form a weak bound state in the vicinity of surface by the action of image charges of individual electrons in front of the surface, the image charge which is analogous to one induced at the metal surface, but the magnitude is very much smaller. The surface state electrons on liquid helium is known to form the Wigner solid, a pure electron lattice. In this seminar, we report about peculiar transport properties of the Wigner solid on a liquid He surface. In addition, the investigation of superfluid helium-3 surface by means of surface state electrons and ions may be briefly mentioned.
讲座题目二:The Kondo Effect – from Spin to Orbital Degrees of Freedom
演讲人:Juhn-Jong Lin教授
NCTU–RIKEN Joint Research Laboratory, Institute of Physics
National Chiao Tung University (Taiwan)
The Kondo effect is a long-standing paradigmatic many-body problem in condensed matter physics. The recent progresses in nanoscience and technology has further made possible new realizations of exotic Kondo physics. In this talk, I will discuss some experimental aspects of (1) the standard Kondo effect due to the existence of isolated localized spin-half magnetic moments, and (2) the two-impurity Kondo effect featured quantum critical behaviors of the transport properties. (3) I will briefly discuss our observation of nonmagnetic Kondo effect due to two-level tunneling systems. In this case, the Kondo physics originates from the coupling of the electronic orbital wavefunctions with dynamical structural defects.
References:
[1] A. M. Chang and J. C. Chen, Rep. Prog. Phys. 72, 096501 (2009). (A review)
[2] S. S. Yeh and J. J. Lin, Phys. Rev. B 79, 012411 (2009); and to be published.
作者简介:
Professor Juhn-Jong Lin (林志忠) received his BS degree from National Chiao Tung University (NCTU, 台灣交通大學) in 1979, and his PhD degree from Purdue University (USA) in 1986. He was an associate professor and a professor in the Department of Physics at National Taiwan University from 1988 to 1997. He joined the Institute of Physics of NCTU in 1997. His research efforts focus on low temperature physics, mesoscopic physics, nanoscale physics, and disordered electronic systems. Website: http://web.it.nctu.edu.tw/~jjlin/
讲座地点:3教104室
讲座时间:2016年6月21日下午2点30分
邀请人:张国权,曹学伟
欢迎老师和同学莅临。