visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
날짜 2016-10-18 13:30 
일시 Oct. 18 (Tue.), 1:30 PM 
장소 1st fl. #1323(E6-2) 
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 날짜 장소 제목
212 2019-02-25 16:00  Rm. 1501 (E6)  Spring 2019: Physics Colloquium file
211 2019-02-21 16:00  #5313, E6-2  B-meson charged current anomalies - Theoretical status file
210 2019-01-23 16:00  Rm. C303, Creation Hall (3F), Munji Campus  Ultrasensitive Microwave Bolometer: Opportunity for Axion Detectors file
209 2019-01-09 16:00  E6-2. 2nd fl. #2501  Molecular Mott state in the deficient spinel GaV4S8 file
208 2019-01-07 15:00  E6-2. 2st fl. #2501  Many-Body Invariants for Multipoles in Higher-Order Topological Insulators file
207 2018-12-27 16:00  E6-2. 1st fl. #1323  Quantum Innovation (QuIN) Laboratory file
206 2018-12-26 16:00  E6-1. 3rd fl. #3434  Informal Workshop on Topology and Correlation file
205 2018-12-26 16:00  E6-2. 1st fl. #1323  Brane-like defect in 3D toric code file
204 2018-12-16 16:00  E6-2. 1st fl. #1323  Lectures on 2d Conformal Field Theory file
203 2018-12-11 16:00  E6-2. 1st fl. #1323  Natural compact representation of Matsubara Green’s functions: applications to analytic continuation and quantum many-body simulations file
202 2018-12-07 16:00  E6-2. 1st fl. #1323  Novel probes of interacting electrons in 2D systems file
201 2018-12-07 14:30  E6-2. 1st fl. #1323  Spin generation from heat and light in metals file
200 2018-11-29 16:00  #1323, E6-2  양자 칸델라 실현을 위한 단일 광자 발생장치 개발 file
199 2018-11-23 15:00  E6-2. 2st fl. #2501  Entanglement string and Spin Liquid with Holographic duality file
198 2018-11-22 15:00  E6 Room(#1323)  Experimental and Computational Study on Physical Properties based on Granular System file
197 2018-11-21 15:00  #1323, E6-2  Engineering topological quantum physics at the atomic scale file
196 2018-11-09 16:00  E6-2. 1st fl. #1323  Quantum sensing and imaging with diamond defect centers for nano-scale spin physics file
195 2018-11-09 14:30  E6-2. 1st fl. #1323  Moiré superlattices – from twisted bilayer graphene to quasicrystal file
194 2018-11-08 16:00  #1323, E6-2  Conformality lost file
193 2018-11-01 16:00  #1323, E6-2  Direct holography from a single snapshot file