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 2019/09/18 - 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
189 September 20 (Thu.), 16:00  #1323, E6-2  Prof. Joo-Hiuk Son  Toward Cancer Treatment Using Terahertz Radiation: Demethylation of Cancer DNA file
188 October 18 (Thu.), 16:00 PM  #1323, E6-2  Prof. Jongseok Lee  Applications of nonlinear optics for condensed matter researches file
187 May 9 (Wed.), 04:00 PM  #1323, E6-2  Prof. Jong-Soo Rhyee  Recent advances in thermoelectric bulk composites file
186 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
185 Jul. 28 (Thu.) 4PM  #1323(E6-2. 1st fl.)  Prof. Johannes Pollanen, Jerry Cowen Chair of Experimental Physics at Michigan State University  Low Dimensional Electrons: On the Road to Hybrid Quantum Systems
184 April 23 (Tue.), 4:00 PM  #1323, E6-2  Prof. Johan Chang  From Mott physics to high-temperature superconductivity file
183 October 22 (Tue.), 10:00am  #1323 (E6-2, 1st fl.)  Prof. Jieun Lee  Harnessing electrons and photons in 2D crystals file
182 Dec. 15 (Fri.), 9:20 AM  E6-2, Lecture Room #1323  Prof. Jhinhwan Lee 외 9명  Workshop on Magnetism in Unconventional Superconductors 개최 file
181 May 29 (Tue.), 04:00 PM  #1323, E6-2  Prof. Jae-Won Jang  Investigation on metal nanostructure/semiconductor junction and its applications file
180 July 13, 2018 at 14:00  Room 5318, KAIST Natural Sciences Lecture Hall(E6).  Prof. Ian Lewis (The University of Kansas, Department of Physics & Astronomy)  Loop Induced Single Top Partner Production and Decay at the LHC
179 DEC. 11 (Tue), 04:00 PM  E6-2. 1st fl. #1323  Prof. Hiroshi Shinaoka  Natural compact representation of Matsubara Green’s functions: applications to analytic continuation and quantum many-body simulations file
178 AUG. 31 (Thu.), 2 PM  #5318(E6-2. 5th fl.)  Prof. Hiroaki Ishizuka (The University of Tokyo)  “Berry phase and nonlinear response: photocurrent in noncentrosymmetric insulators and Weyl semimetals” file
177 May 31 (Fri.), 11:00 AM  #1323, E6-2  Prof. Guido Burkard  Cavity QED with Spin Qubits file
176 2015/07/23,1:30PM  E4, B401  Prof. Gilles Lérondel (Univ. of Technology of Troyes)  Enhanced ZnO based UV photonics and related applications file
175 February 21 (Thu.), 16:00 PM  #5313, E6-2  Prof. Diptimoy Ghosh  B-meson charged current anomalies - Theoretical status file
174 2016/03/07-06/13  E6, 1501  Prof. David Helfman(KAIST) 외  Physics Colloquium : 2016 Spring file
173 2015/03/04, 12PM  1323호, E6-2  Prof. Choi Hak-Soo(Harvard)  Bioimaging and Biosensing Using Near-Infrared Fluorescence file
172 May. 3 (Fri), 11:00 AM  E6-2. 2st fl. #2502  Prof. Changhee Sohn  Exotic Magnetism file
171 2014/12/22, 2PM  E6, Rm1319  Prof. Changbong Hyeon (KIAS)  Dynamics of molecular motors: Power stroke vs Brownian ratchet file