11시부터 랩 투어,

오후 1:30에 세미나

제 목 Ultrafast imaging of vibrations in plasmonic and phononic structures

강 사 Prof. Oliver Bernard Wright

소 속 Hokkaido University, Japan

시 간 2011년 5월 24일 (화요일) 오후 1시 30분

장 소 제1 신공학관 301동 1112호

Abstract

Plasmonic crystals, periodic nanostructures than couple electrons in a solid and light together, are the subject of a recent boom in interest because of the possibility of controlling visible light on the nanoscale. At the same time phononic crystals are also the subject of a similar boom because of their potential for filtering GHz electrical signals by their conversion to surface acoustic waves. Here I present measurements using an ultrafast optical technique of vibrations in plasmonic and phononic crystals. I show how animations of the surface vibrations can be obtained at various frequencies. This research could result in the new field of "plasphonics".

강사이력

O. B. Wright initially specialized in low temperature solid state physics. Over the period 1982-1984 he published a detailed account of the thermoelastic effect in glasses at low temperatures—a modern version of a rubber band experiment in which the temperature change of the band is monitored on stretching.

After obtaining an industrial post he concentrated on applications of optics in sensor physics, in particular specializing in the use of ultrashort optical pulses for generating and detecting picosecond acoustic phonon pulses in thin films and multilayers. In 1992 he developed a related phonon pulse detection technique based on the measurement of picosecond surface motion. With this technique in 1994 he demonstrated how ultrafast electron diffusion could be probed in metals, and in 1998 he contributed to the development of a theory of this diffusion, establishing an analytical relationship between the electron energy relaxation time and the electron-phonon and electron-electron coupling strengths.

Focusing in 2001-2002 on semiconductors, he measured the shape of picosecond acoustic phonon pulses generated in gallium arsenide, and was involved in similar spectroscopic experiments on semiconductor quantum wells. In 2002 he also helped establish a method for watching ripples on crystals using ultrafast interferometry. He has also worked on the development of ultrasonic force microscopy and new local probe imaging techniques for thermal waves at high frequencies on nanometre length scales, as well as making contributions to the theory of the detection of phonon pulses in multilayers.

More recently he has been involved in extending picosecond ultrasonics to shear waves and to liquids, as well as spending time watching ripples travelling on phononic crystals and resonators.

QUALIFICATIONS

· BA Physics, University College, Oxford, UK, July 1978

· PhD Physics, King's College, Cambridge, UK, Feb. 1982

EDUCATION AND EMPLOYMENT

· Low Temperature Physics Group, Cavendish Laboratory, Cambridge, UK, PhD. Title of thesis: 'Thermoelastic effects in glasses'

· Centre de Recherche sur les Tres Basses Temperatures, CNRS, Grenoble, France (Mar. 1982 to Aug. 1983) Royal Society Fellowship

· Schlumberger Montrouge Research, France (Sept. 1983 to Nov. 1986) Ingenieur

· Nippon Steel Corp., Electronics Research Laboratories, Sagamihara, Japan (Dec. 1986 to Feb. 1994) Senior Researcher

· CNR, Istituto di Acustica "O. M. Corbino", Rome, Italy (Mar. 1994 to Apr. 1995) EU Human Capital and Mobility Senior Fellowship

· Laboratoire de Physique et Metrologie des Oscillateurs, CNRS, Besancon, France (May 1995 to April 1996) Ingenieur de Recherche

· Dept. of Applied Physics, Faculty of Engineering, Hokkaido University, Japan (from May 1996) Professor

PROFESSIONAL SOCIETY MEMBERSHIP

· Fellow of the Institute of Physics

· Optical Society of America

· American Institute of Physics

· Physical Society of Japan 문의처 : 이병호 교수