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 1078566
385 <9/17(수)> Reshaping Micro/Nanophotonics by Programmable Soft-Matter 2014.09.15 68454
384 2014학년도 2학기 콜로퀴움 일정 2014.09.11 106691
383 <9/23(화)> Novel resistive switching behavior of ferroelectric nanodevices file 2014.09.03 59244
382 <9/11(목)> The effects of dark matter elastic scattering on the cosmological signals 2014.09.01 66831
381 <7/21(월)> The rapid neutron capture nucleosynthesis: A hot topic in the Nuclear Astrophysics study 2014.07.15 120371
380 <5/30(금)> 입자물리이론 그룹 미니 워크숍 개최 안내 2014.05.29 102945
379 <6/11> Advanced Physiological Optics and Its Ophthalmic Applications 2014.05.28 257997
378 <5/28> The hunt for high energy neutrinos with IceCube - more evidence for their astrophysical origin 2014.05.22 112621
377 <5/21> Magnetism and Superconductivity 2014.05.14 113177
376 <5/14> Synthesis of Two Dimensional Materials by Chemical vapor deposition 2014.05.07 94242
375 <5/7> Contribution of Internal and Surface Traps to Blinking Statistics in Colloidal Quantum Dots 2014.04.30 90742
374 <4/30> Physical principles and applications of ultrasound in diagnostics and therapy 2014.04.22 69936
373 <4/16> Lasers, Microscopes, and Superconductors: Laser Scanning Microscopy of Superconducting Circuits 2014.04.10 109603
372 <4/9> Quantum oscillations at the LHC 2014.04.03 104107
371 <4/2> Radio Detection of Ultra High Energy Cosmic Rays and Neutrinos in Antarctica 2014.03.26 177510
370 <3/26> Shedding infrared light on high-Tc superconductors 2014.03.19 113850
369 <3/19> 고자기장 하에서 반도체 양자구조의 광전이 특성 2014.03.13 75018
368 <3/12> Where, when and how atomic nuclei were cooked in universe? 2014.03.07 89549
367 2014학년도 1학기 콜로퀴움 일정 2014.03.03 104204
366 <12/11> Is Nature Natural? 2013.12.05 67452