visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
장소 E6-2, #1323 
일시 2015/12/11, 1:30PM 
연사 Dr. KwangYong Choi  (Chung-Ang University) 

Quantum spin liquid in the 1/3 depleted triangular lattice Ba3(Ru1-xIrx)Ti2O9

 

Dec. 11. (Fri.), 13:30 PM,  E6-2. 1st fl. #1323
Dr. KwangYong Choi  (Chung-Ang University)

 

Geometrically frustrated antiferromagnets are a versatile reservoir for emergent quantum-correlated phenomena such as spin liquids, fractionalized excitations, and magnetic monopoles. Recent experiments on the 6H-perovskite family Ba3AB2O9 (A=Cu, Ni, Co, Ru, Ir; B=Sb, Ti) have disclosed a variety of interesting ground states: a random singlet, spin liquid, spin freezing, and 120? ordering, depending on a spin number, spin-orbit coupling, and Jahn-Teller (JT) distortions. In this talk, I will briefly introduce spin liquid in the context of topological order and then present experimental results on the two materials Ba3CuSb2O9 and Ba3Ru1-xIrxTi2O9. In Ba3CuSb2O9, a combined effect of frustration and local JT distortions may create a novel spin-orbital entangled state. Our ESR results provide evidence for intrinsic coupling of spins to orbital degrees of freedom and thereby demonstrate that magnetism is dictated by a spatiotemporal structure of the JT distortions. In Ba3Ru1-xIrxTi2O9, a 1/3 depleted triangular lattice with strong spin-orbit coupling we address the possibility of spin-orbit tuned spin liquids. For the 4d Ru compound, we find experimental signatures of a coexisting spin freezing and dynamically fluctuating state. In the 5d Ir counterpart, spin-orbit coupling melts residual spin freezing while stabilizing a spin liquid state. Our comparative study evidences that spin depletion and spin-orbit coupling conspire to promote a quantum spin liquid in triangular antiferromagnets.

 

Contact: Heung Sun Sim, Physics Dept., (hs_sim@kaist.ac.kr)

번호 일시 장소 연사 제목
공지 2019/03/21 - 5/30  Seminar Room #1323  Dr. Hyangtag Lim (KIST) and etc.  Spring 2019: Physics Seminar Serises
공지 2019/02/25 - 06/03  Seminar Room 1501  양용수 교수 (Prof. Yongsoo Yang, KAIST) and etc.  Spring 2019: Physics Colloquium
25 2015/08/04, 11PM  B501, Room Red, KI bldg. 5nd fl.  Dr. Eric Jin Ser Lee(Univ. of Manitoba, Canada)  Propagation of ultrasound through two- and three-dimensional strongly scattering media
24 2015/07/23,1:30PM  E4, B401  Prof. Gilles Lérondel (Univ. of Technology of Troyes)  Enhanced ZnO based UV photonics and related applications file
23 2015/07/16-07/17  E6-2, 1501  Sang-Wook Cheong (Rutgers Univ.)  KAIST Physics Distinguished Lecture
22 2015/07/15, 2PM  E6-2,1323  Dr. Se Young Park(Rutgers Univ.)  Electronic and optical properties of titanate-based oxide superlattices
21 2015/07/16, 4PM  E6-2, 1318  Dr. Kyunghan Hong(MIT)  Next-generation ultrafast laser technology for nonlinear optics and strong-field physics
20 2015/06/03, 12PM  Room 101, E11  Prof. Min-Kyo, Seo & Hansuek, Lee(KAIST)  The First Wednesday Multidisciplinary Forum file
19 2015/03/09-06/08  E6, 1501  최현용교수(연세대) 외12명  Physics Colloquium : 2015 Spring file
18 2015/03/13, 2PM  Connect Room, KI Bldg.    The 15th Innovative Workshop on Soft/Bio Materials file
17 2015/03/04, 12PM  1323호, E6-2  Prof. Choi Hak-Soo(Harvard)  Bioimaging and Biosensing Using Near-Infrared Fluorescence file
16 2014/12/22, 2PM  E6, Rm1319  Prof. Changbong Hyeon (KIAS)  Dynamics of molecular motors: Power stroke vs Brownian ratchet file
15 2015/09/15-12/08  E6, 1501  박제근 교수(서울대 물리학과) 외12명  Physics Colloquium : 2014 Fall file
14 2014/05/28, PM5  KI Building, Matrix Hall  이웅범 대표이사(LG이노텍)  부품소재산업이 미래다
13 2014/03/10-06/09  E6, 1501  신용일교수(서울대)  Physics Colloquium : 2014 Spring file
12 2013/09/09-12/09  E6, 1501  박혁규교수(부산대) 외  Physics Colloquium : 2013 Fall
11 2013/03/11-06/10  E6, 1501  강명수교수(KAIST) 외  Physics Colloquium : 2013 Spring
10 2012/04/02, 4PM  E6, 1501  Yong Hee Jeong  A new route to ferroelectricity in magnetic spinels: a case of Co2MnO4
9 2012/02/13-05/14  E6, 1501  Kenji Ohmori (Photo-Molecular Science, IMS)  Physics Colloquium : 2012 Spring
8 2011/09/03-12/06  E6, 1501  김용균교수(한양대) 외  Physics Colloquium : 2011 Fall file
7 2011/05/16, 4PM  E6, 1501  서민교교수(KAIST)  Photonics with surface plasmon polaritons
6 2010/02/14-05/09  E6, 1501  황철주(주성엔지니어링 사장) 외  Physics Colloquium - 2011 Spring file