• 메인
  • >
  • 소식
  • >
  • 세미나
장소 #1323(E6-2. 1st fl.) 
일시 Feb. 1 (Wed.), 2p.m. 
연사 Dr. Michihisa Yamamoto, Department of Applied Physics, The University of Tokyo 

Quantum electron optics using flying electrons


Dr. Michihisa Yamamoto, Department of Applied Physics, The University of Tokyo

Feb. 1 (Wed.), 2p.m.  #1323(E6-2. 1st fl.)


Abstract: Quantum electron optics is a field in which one manipulates quantum states of propagating electrons. Combined with technologies for confining and manipulating single electrons, it allows us to investigate the scattering and interference of electrons in a unit of a single electron. The necessary elements of quantum electron optics experiments include single electron beam splitter, phase shifter, Coulomb coupler, single electron source and detector, spin-orbit path and electron-pair splitter.

In this talk, we present development of some of these elements. The beam splitter and phase shifter are implemented in our original two-path interferometer [1-3]. This interferometer has been shown to be the only reliable system for the measurement of the transmission phase shift of electrons [4,5]. To suppress decoherence induced by the electron-electron interaction and enhance the interference visibility, we recently developed a two-path interferometer of depleted channels, where single electrons are injected by means of surface acoustic waves (SAWs). We also confirmed that a single electron in a static quantum dot (single electron source) can be adiabatically transferred into a SAW-driven moving quantum dot [6], a necessary ingredient for achieving the high interference visibility of a single flying electron.

Quantum electron optics also targets the manipulation of spins of flying single electrons. We found that the spin information of one or two electrons can be transferred between distant quantum dots, which work as the single electron source and detector, with the fidelity limited only by the spin flips prior to the spin transfer [7,8]. We also realized an electron-pair splitter that can be used to split spin-entangled electrons in a moving dot into different moving dots. Combined with single spin manipulation using the spin-orbit interaction (spin-orbit path) [9], this splitter should allow for Bell measurement of electron spins.

This work is in collaboration with S. Takada (now at Institut Neel), R. Ito and K. Watanabe at the University of Tokyo, B. Bertrand, S. Hermelin, T. Meunier, and C. Bäuerle at Institut Neel, and A. Ludwig and A. D. Wieck at Ruhr-Universität Bochum.


[1] M. Yamamoto et al., Nature Nano. 7, 247 (2012)..

[2] A. Aharony et al., New J. Phys. 16, 083015 (2014).

[3] T. Bautze et al., Phys. Rev. B 89, 125432 (2014).

[4] S. Takada et al., Phys. Rev. Lett. 113, 126601 (2014).

[5] S. Takada et al., Appl. Phys. Lett. 107, 063101 (2015).

[6] B. Bertrand et al., Nanotechnology 27, 204001 (2016).

[7] S. Hermelin et al., Nature 477, 435 (2011).

[8] B. Bertrand et al., Nature Nano. 11, 672 (2016).

[9] H. Sanada et al., Nature Phys. 9, 280 (2013).


Contact: SunYoung Choi, (



Center for Quantum Coherence in Condensed Matter, KAIST

번호 일시 장소 연사 제목
공지 2017/09/14 - 12/07  Seminar Room #1323  Prof. 정광용 교수(Gacheon Univ) and etc.  Fall 2017: Physics Seminar Serises
공지 2017/09/04 - 12/04  Seminar Room 1501  Prof. Sangsu Bae(Hanyang Univ.) and etc.  Fall 2017: Physics Colloquium
141 5월 17일(화), 11:00 ~ 12:00  창의학습관(E11), 406호  방준혁 박사(Korea Basic Science Institute, KBSI)  The CERN Resonant WISP Search: Development, Results and Lesson-Learned
140 Apr. 27, 2017 (Thu) 4:00 pm  Seminar Room(#1323, E6-2)  Prof.Donghan Lee (Chungnam National Univ.)  반도체 양자점을 이용한 단광자 광원
139 2017/03/06 - 05/29  Seminar Room 1501  이종봉 박사 (POSTECH) 외  Spring 2017: Physics Colloquium file
138 2017/03/21 - 06/08  Seminar Room 1323  조길영 박사(KAIST) 외  Spring 2017: Physics Seminar Serises file
137 Jun. 14 (Tue) 4PM  Seminar Room (#2502, 2nd fl.)  Young-Sik Ra, Université Pierre et Marie Curie  Photonic quantum network based on multimode squeezed vacuums and single-photon subtraction
136 Nov. 1 (Tue.) 2:30 pm  Seminar Room #1323(E6-2)  Prof. Youngjoon Kwon, Yonsei Univ.  Search for dark sector particles in the B-factory experiments
135 2015/06/03, 12PM  Room 101, E11  Prof. Min-Kyo, Seo & Hansuek, Lee(KAIST)  The First Wednesday Multidisciplinary Forum file
134 April 5th 2017, 12:00 ~ 13:00  Room 101, Creative Learning Bldg.(E11)  Prof. Wonho Choe(Dept. of Physics),Prof. Young-chul GHIM(Dept. of Nuclear & Quantum Engineering)  2017년 4월 첫수 융합포럼 개최 안내(물리학과 & 원자력 및 양자공학과 공동 개최)/The First Wednesday Multidisciplinary Forum in April 2017 organized by Dept. of Physics & Dept. of Nuclear & Quantum Engineering file
133 2016/09/05-12/12 4PM  Natual Scien Bldg.(E6)m #1501  Yeong Kwan Kim 외  Physics Colloquium : 2016 Fall file
132 May 19, 2016 (Thur.) 3PM  May 19, 2016 (Thur.) 3PM,  Dr. Michael Betz, CERN  The CERN Resonant WISP Search: Development, Results and Lesson-Learned
131 2017.1.9(Mon), 4PM  Lecture Hall, College of Natural Sciences [#1501,E6-2]  Prof. John Michael Kosterlitz, Brown University  Topological Defects and Phase Transitions" file
130 4월 18일(월), 15:30~  KI빌딩(E4), 강의실 B501 (5F)  Prof. Robert A. DiStasio Jr. (Cornell University)  First Principles Approaches for Intermolecular Interactions: From Gas-Phase Dimers to Liquid Water and Molecular Crystal Polymorphism file
129 2014/05/28, PM5  KI Building, Matrix Hall  이웅범 대표이사(LG이노텍)  부품소재산업이 미래다
128 Aug. 4, 2016 (Thu.), 2:30 pm  KAIST Natural Science Building (E6-5), EDU 3.0 Room(1st fl.)  Prof. Argyris Nicolaidis  Relational Logic (with applications to Quantum Mechanics, String Theory, Cosmology, Neutrino Oscillations, Statistical Mechanics)
127 April 4, 2016 (Mon) - April 8, 2016 (Fri)  KAIST Natural Science Building (E6-2), RM #4314  Dr. Fritz Caspers (CERN)  Radio frequency engineering
126 2015/10/14, 6PM  KAIST Munji Campus Supex Hall  이창환 교수 (부산대학교 물리학과)  인터스텔라 영화 속의 물리 file
125 #1323(E6-2. 1st fl.)  Jul. 10th (Mon), 4pm  Dr. Duk Young Kim Los Alamos National Laboratory  “Intertwined Orders in a Heavy-fermion metal” file
124 April 6, 2017 (Thu), 4:00 pm  IBS CAPP seminar room, Creation Hall (3F), KAIST Munji Campus  Prof. Youngjoon Kwon (Yonsei University)  For whom the Belle tolls