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
506 2013-03-11 16:00  E6, 1501  Physics Colloquium : 2013 Spring
505 2013-09-09 16:00  E6, 1501  Physics Colloquium : 2013 Fall
504 2014-03-10 16:00  E6, 1501  Physics Colloquium : 2014 Spring file
503 2014-05-28 17:00  KI Building, Matrix Hall  부품소재산업이 미래다
502 2014-12-22 14:00  E6, Rm1319  Dynamics of molecular motors: Power stroke vs Brownian ratchet file
501 2015-03-04 12:00  1323호, E6-2  Bioimaging and Biosensing Using Near-Infrared Fluorescence file
500 2015-03-09 16:00  E6, 1501  Physics Colloquium : 2015 Spring file
499 2015-03-13 14:00  Connect Room, KI Bldg.  The 15th Innovative Workshop on Soft/Bio Materials file
498 2015-06-03 12:00  Room 101, E11  The First Wednesday Multidisciplinary Forum file
497 2015-07-15 14:00  E6-2,1323  Electronic and optical properties of titanate-based oxide superlattices
496 2015-07-16 16:00  E6-2, 1318  Next-generation ultrafast laser technology for nonlinear optics and strong-field physics
495 2015-07-16 16:00  E6-2, 1501  KAIST Physics Distinguished Lecture
494 2015-07-23 13:30  E4, B401  Enhanced ZnO based UV photonics and related applications file
493 2015-08-03 10:30  E6-2, #1323 (Seminar Room)  Axion Search
492 2015-08-04 11:00  B501, Room Red, KI bldg. 5nd fl.  Propagation of ultrasound through two- and three-dimensional strongly scattering media
491 2015-09-07 15:00  E6-2. 1st fl. #1318  Advanced Optical Materials and Devices at NRL
490 2015-09-07 16:00  E6, 1501  Physics Colloquium : 2015 Fall file
489 2015-09-14 14:00  E6-2. 2nd fl. #2501  Ultrafast X-ray Studies on Dynamics Matter in Extreme Conditions
488 2015-09-15 16:00  E6, 1501  Physics Colloquium : 2014 Fall file
487 2015-10-14 18:00  KAIST Munji Campus Supex Hall  인터스텔라 영화 속의 물리 file