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
502 2016-07-08 11:00  #1323(E6-2. 1st fl.)  Isostatic magnetism
501 2016-11-11 13:30  #1323(E6-2. 1st fl.)  Bandgap Engineering of Black Phosphorus
500 2016-07-07 14:00  #1323(E6-2. 1st fl.)  Let there be topological superconductors
499 2017-02-01 14:00  #1323(E6-2. 1st fl.)  Quantum electron optics using flying electrons
498 2016-11-16 16:00  #1323(E6-2. 1st fl.)  Realizing Haldane Model in Fe-based Honeycomb Ferromagnetic Insulators
497 2018-10-19 10:00  #1323, E6-2  Energy conversion processes during magnetic reconnection in a laboratory plasma file
496 2018-05-31 16:00  #1323, E6-2  Dynamic control of optical properties with gated-graphene metamaterials file
495 2018-10-04 16:00  #1323, E6-2  Engineering light absorption in an ultrathin semiconductor metafilm file
494 2019-12-05 16:00  #1323, E6-2  Subwavelenth Photonic Devices: From Single Photon Sources to Solar Cell file
493 2019-10-15 16:00  #1323, E6-2  Moiré superlattices and graphene quasicrystal file
492 2018-10-16 10:00  #1323, E6-2  Capturing protein cluster dynamics and gene expression output in live cells file
491 2019-11-05 16:00  #1323, E6-2  Study on nanomaterials by the development of ultrahigh resolution laser-photoelectron microscopy (PEEM) file
490 2018-11-01 16:00  #1323, E6-2  Direct holography from a single snapshot file
489 2019-12-18 16:00  #1323, E6-2  Road to Higher Tc Superconductivity file
488 2018-05-09 16:00  #1323, E6-2  Recent advances in thermoelectric bulk composites file
487 2018-11-21 15:00  #1323, E6-2  Engineering topological quantum physics at the atomic scale file
486 2018-10-11 16:00  #1323, E6-2  Dirac electrons in a graphene quasicrystal file
485 2019-10-25 15:00  #1323, E6-2  Physics Seminar file
484 2019-09-18 16:00  #1323, E6-2  Exploring Synthetic Quantum Matter in Superconducting Circuits file
483 2018-10-15 16:00  #1323, E6-2  Universal properties of macroscopic current-carrying systems file