visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
장소 1st fl. #1323(E6-2) 
일시 Oct. 18 (Tue.), 1:30 PM 
연사 Dr. Chan-Ho Yang, Department of Physics, KAIST 

"Visualization of oxygen vacancy in motion and the interplay with electronic conduction"

 

Dr. Chan-Ho Yang, Department of Physics, KAIST
Oct. 18 (Tue.), 1:30 PM, 1st fl. #1323(E6-2)


Abstract:

The multiferroic BiFeO3 (BFO) is an interesting playground to explore correlated electronic conduction. Here, we substitute divalent Ca ions into the parent BFO and apply an external electric field at elevated temperatures to spatially redistribute spontaneously created oxygen vacancies, thereby generating hole carriers in regions of less dense oxygen vacancy concentrations. X-ray diffraction and photoemission spectroscopic measurement are employed to quantify a large variation of local oxygen vacancy concentration as much as ~1021 cm-3 and explore the consequent evolution of electronic band structure. We find that a non-rigid polaronic band is created by hole doping as a result of a strong electron-lattice coupling. We also show strong evidence for the disorder-driven formation of a Coulomb glass state through electronic transport measurement on a quantitative level. These spectroscopic and transport results can be combined and understood in the framework of intrinsic spatial inhomogeneity of polaronic charge density. Dynamical properties of oxygen vacancy in motion will be also discussed in a spatial-resolved way. The finding offers a promising platform and methodology for examining the interplay of functional defects and correlated electronic behaviors.

 

Contact: SunYoung Choi, (sunyoungchoi@kaist.ac.kr)
Center for Quantum Coherence in Condensed Matter, KAIST

번호 일시 장소 연사 제목
공지 2019/09/18 - 12/5  Seminar Room #1323  Prof. David Schuster and etc.  Fall 2019: Physics Seminar Serises
공지 2019/09/02 - 12/09  Seminar Room 1501  이호성 박사 (한국표준과학연구원) and etc.  Fall 2019: Physics Colloquium
17 Oct. 07 (Fri), 4:00 PM  E6-2. #1323(1st fl.)  Dr. Choong Hyun Kim,IBS-CCES, Seoul National University  “Tilt engineering of 4d and 5d transition metal oxides?”
16 Apr. 08 (Fri.), 4:00 PM  E6-2. 5st fl. #1501  Dr. Changyoung Kim, SEOUL NATIONAL UNIV.  Spectroscopic studies of iron-based superconductors : what have we learned?
15 Sep. 4 (Tue), 02:30 PM  E6-2. 2st fl. #2502  Dr. Changmin Lee, MIT  Ultrafast time- and angle-resolved photoemission spectroscopy (tr-ARPES) with extreme ultraviolet laser pulses file
14 Apr. 28 (Thu.) 3PM  #2501(E6-2. 2nd fl.)  Dr. Chang Hee Sohn, SEOUL NATIONAL UNIVERSITY  Lattice/Spin/Charge Coupling in 5d Pyrochlore Cd2Os2O7
» Oct. 18 (Tue.), 1:30 PM  1st fl. #1323(E6-2)  Dr. Chan-Ho Yang, Department of Physics, KAIST  "Visualization of oxygen vacancy in motion and the interplay with electronic conduction"
12 JAN. 7 (Mon), 03:00 PM  E6-2. 2st fl. #2501  Dr. Byoung min Kang  Many-Body Invariants for Multipoles in Higher-Order Topological Insulators file
11 Feb. 12 (Mon), 3:00pm  #C303, (Creation Hall 3F, KAIST Munji Campus)  Dr. Byeongsu Yang, Kamioka Observatory, Univ. of Tokyo  The recent result of XMASS Experiment
10 May 11 (Wed.), 4 PM  E6-2. #1323(1st fl.)  Dr. Bumjoon Kim, Max Planck Institute for Solid State Research  The quest for novel high-temperature superconductors---Prospects and progress in iridates
9 Jun 28, 14:00  E6-2, #1322  Dr. Bongjae Kim, Dr. Sooran Kim, Dr. Jeongwoon Hwang  1st Research-exchange meeting of computational material physics file
8 Nov. 11th (Fri), 4 p.m.  #1323(E6-2. 1st fl.)  Dr. Bohm-Jung Yang, SNU  Dirac fermions in condensed matters
7 2016/1/11, 4PM  E6-2, #1323  Dr. B.J.Kim (Max Planck Institute for Solid State Research)  Mott Physics in the Strong Spin-Orbit Coupling Regime
6 Apr. 5 (Tue.), 4PM  E6-2. 1st fl. #1322  Dr. Ara Go, Columbia University  A new impurity solver for multi-orbital systems: adaptive truncation of the Hilbert space
5 April 6, 2016 (Wed), 3:30 PM  E6-2, RM #1323  Dr. Andrei Matlashov (Los Alamos National Laboratory)  Superconducting Quantum Interference Devices for Precision Detection
4 Dec. 12th (Mon)  1:30p.m. #1323(E6-2. 1st fl.)  Dongjoon Song , AIST  “Possible symmetry in the phase diagrams of electron- & hole-doped cuprate high-Tc superconductors”
3 Thursday, December 14, 2017 at 3:00 pm  Seminar Room (C303), Creation Hall (3F), KAIST Munji Campus  Chunglee Kim (KASI)  Exploring the Universe via GWs in the era of multi-messenger astronomy
2 2015/12/09, 2PM  E6-2, #1323  Arjun G. Yodh (University of Pennsylvania)  SWELLABLE COLLOIDAL PARTICLES ARE SWELL
1 2015/12/09, 11AM  E4(KI Building), Connect room (2nd fl.)  Arjun G. Yodh (University of Pennsylvania)  Functional Imaging & Monitoring of Brain & Breast with Diffuse Light