visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
날짜 2015-12-11 13:30 
일시 2015/12/11, 1:30PM 
장소 E6-2, #1323 
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 날짜 장소 제목
188 2018-10-18 16:00  #1323, E6-2  Applications of nonlinear optics for condensed matter researches file
187 2018-10-18 10:00  #1323, E6-2  Understanding membrane protein folding using single-molecule force techniques file
186 2018-10-16 10:00  #1323, E6-2  Capturing protein cluster dynamics and gene expression output in live cells file
185 2018-10-15 16:00  #1323, E6-2  Universal properties of macroscopic current-carrying systems file
184 2018-10-12 16:00  E6-2. 1st fl. #1323  Direct observation of a two-dimensional hole gas at oxide interfaces file
183 2018-10-12 14:30  E6-2. 1st fl. #1323  Quantum Advantage in Learning Parity with Noise file
182 2018-10-11 16:00  #1323, E6-2  Dirac electrons in a graphene quasicrystal file
181 2018-10-04 16:00  #1323, E6-2  Engineering light absorption in an ultrathin semiconductor metafilm file
180 2018-09-20 16:00  #1323, E6-2  Toward Cancer Treatment Using Terahertz Radiation: Demethylation of Cancer DNA file
179 2018-09-07 15:00  학술문화관 (E9), 2층 양승택 오디토리움  Recent developments in density functional theory: From new functionals to the nature of the chemical bond file
178 2018-09-05 16:00  #1323, E6-2  Shining a light on fractional excitations file
177 2018-09-04 14:30  E6-2. 2st fl. #2502  Ultrafast time- and angle-resolved photoemission spectroscopy (tr-ARPES) with extreme ultraviolet laser pulses file
176 2018-08-01 11:00  양분순 빌딩 (E16-1) 207호  Future of AI: Is the brain a computer? file
175 2018-07-27 15:00  Room 5318, KAIST Natural Sciences Lecture Hall(E6).  Muon g-2 in the 2HDM and MSSM: comprehensive numerical analysis and absolute maxima file
174 2018-07-27 13:30  #1323, E6-2  Magnetic reversal of artificial spin ice file
173 2018-07-26 14:00  Room 5318, KAIST Natural Sciences Lecture Hall(E6).  Inflation in String Theory and Backreaction file
172 2018-07-13 14:00  Room 5318, KAIST Natural Sciences Lecture Hall(E6).  Loop Induced Single Top Partner Production and Decay at the LHC
171 2018-07-12 17:00  Room 5318, KAIST Natural Sciences Lecture Hall(E6)  The MilliQan Experiment: Search for Milli-Charged Particles at the LHC
170 2018-07-09 14:00  #1323, E6-2  The principles of collective learning file
169 2018-07-02 15:00  Seminar Room (C303), Creation Hall (3F), KAIST Munji Campus  High Precision Magnetic Field Measurement for the Muon g-2 Experiment file