korean english


Home > 게시판 > 세미나

아래와 같이 콜로퀴움을 개최하오니 많이 참석해 주시기 바랍니다.

4시 20분부터 제1과학관 31214 e+강의실에서 간단한 다과를 제공합니다.

아 래

Title: Ultrafast Movie Maker for Photo-induced Dynamics: Ultrafast Electron Microscope

Speaker: 장   기   석  박사님 (LG Display)

Date & Time: Mar. 27. (Wed.) 2019 4:30 PM

Place: Natural Science 1,  Room No. 31214

Abstract: Making a ‘molecular movie’ is Holy Grail to directly visualize structural phase transitions among metal, insulator and superconductor and photo-induced non-thermal energy transfer processes. To achieve this, an ‘ultrafast camera’ with simultaneously high spatial and temporal resolution to catch the atomic dynamics is required. The pump-probe technique based on femtosecond pump laser with a electron pulse probe can provide a basic framework for realizing such an ‘ultrafast camera’ although this technology has not achieved its full utility as a universal imaging and spectroscopy tool, due to limitations in generation and preservation of a high–brightness electron beam in the ultrafast regime. To realize the high-brightness electron pulse, the major challenge is overcoming strong Coulomb repulsion among electrons (space-charge effect) in the pulse, because the space–charge effect causes the electron pulse expansion in transverse and longitudinal direction. In this seminar, the high-brightness ultrafast electron beam physics will be introduced with the major components, (1) photoelectron gun, (2) magnetic lenses, and (3) an RF compressor controlling the space-charge effect along transverse and longitudinal direction respectively, and the previous studies about photo-induced surface charge dynamics and structural phase transition in graphene and VO2 will be presented.

번호 제목 날짜 조회 수
공지 <12/8(Thu.) 11:00am>노벨상 소개 강연 - 2016년 노벨 물리학상: 위상 응집 물리의 탄생 2016.11.28 1058335
226 <9/12> Observation of Higgs Particle at CERN 2012.09.07 82516
225 <9/21> Electronic phase transition in low dimensional SrTiO3/(Sr1-x,Lax)TiO3 oxide superlattices 2011.09.09 82493
224 2013학년도 2학기 콜로퀴움 일정 2013.09.06 82392
223 <Sep. 7(Wed.) 4:30 PM>Manipulating spins in topological insulators 2016.09.02 82245
222 <11/12> 다윈의 식탁 - 현대 진화론의 맛있는 논쟁 2010.11.05 82158
221 <4/4> Cooking up elements in the universe: Nuclear astrophysics with exotic ion beams 2012.03.29 82085
220 <11/3>고온 초전도와 MgB2 초전도체-미래전망 2006.11.03 81595
219 <May.9(Wed.) 4:30 PM> "How gold was produced in the universe?" 2018.05.02 81506
218 <9/5> Dark Matter and Dark Energy in Cosmology 2008.09.01 81472
217 2006학년도 2학기 콜로퀴움 일정 2006.10.23 81432
216 <11/9> 자기저항 현상과 스핀트로닉스, 그리고 금속성 산화물 자성체 2007.11.05 81376
215 <3/24> 복잡계 네트워크와 경제물리학(Complex Networks and Econo-Physics) 2006.03.20 81259
214 <Nov.18(Wed.)>When Physics meets the Living Cells 2020.11.11 81228
213 <Sep.12(Wed.) 4:30 PM> Functional Nanomaterials for Energy Harvesting 2018.09.05 81174
212 <4/6> Introduction to Superconducting Quantum Electronics 2007.04.03 81109
211 <5/18> Introduction to quantum simulation of materials 2007.05.15 80782
210 <10/12> Introduction to the Proton Engineering Frontier Project 2011.10.10 80777
209 <11/12(수)> Photovoltaic effect and polarization-modulated conduction in ferroelectrics 2014.11.05 80726
208 <11/2>반도체성 나노구조 2007.11.01 80545
207 <9/7> 과학과 예술 (Science and Arts) 2011.08.30 80340