visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
날짜 2017-11-03 16:00 
일시 Nov. 3 (Fri.), 4:00 PM 
장소 #1323 (1st fl., E6-2.) 
연사 Dr. SungDae Ji (Max Planck POSTECH/Hshinchu Center (MPK)) 

The seminal work of Anderson triggered a great deal of theoretical and experimental efforts to search for the novel quantum spin liquid (QSL) states in matters, and it has become one of central issues in contemporary condensed matter physics. The QSL state, a long-range quantum entangled state, is represented by a topological order and fractionalization of constituent magnetic moments. While the most QSL states have been described by deconfined spinons as an elementary excitation in frustrated magnets, Kitaev’s QSL state is exactly derived by fractionalizing the spin excitation into Majorana fermions in a two-dimensional honeycomb lattice, the so-called Kitaev lattice, with the ansatz of bond dependent Ising-like spin interaction. In the past decade, experimental realization of the fascinating Kitaev honeycomb QSL model has been eagerly pursued. In this talk, I will present the experimental evidences of fractionalized Majorana fermions in a high quality α-RuCl3 single crystal. Neutron and x-ray diffraction measurements reveal that the low-temperature crystal structure forms the perfect Ru-honeycomb lattice, which provides an ideal platform for the Kitaev honeycomb quantum spin lattice. Extensive thermodynamic and neutron spectroscopic measurements directly proved fractionalized Majorana fermion excitations as a result of thermal fractionalization of Jeff = ½ pseudospins, which is well reproduces by numerical predictions obtained from the Kitaev model.

 

20171103_지성대.pdf

번호 날짜 장소 제목
459 2019-11-05 16:00  #1323, E6-2  Study on nanomaterials by the development of ultrahigh resolution laser-photoelectron microscopy (PEEM) file
458 2019-11-07 16:00  #1323, E6-2  Integrated quantum photonics with solid-state quantum emitters file
457 2020-01-17 16:00  #1323, E6-2  Symmetry Breaking and Topology in Superfluid 3He file
456 2020-02-20 16:00  #1323, E6-2  Unconventional superconductivity in the locally non-centrosymmetric heavy-fermion CeRh2As2 file
455 2016-10-17 11:00  #1323,(E6-2, 1st fl.)  IMS and examples of the studies on optoelectronic materials
454 2019-09-02 16:00  Seminar Room 1501  Fall 2019: Physics Colloquium file
453 2016-04-28 15:00  #2501(E6-2. 2nd fl.)  Lattice/Spin/Charge Coupling in 5d Pyrochlore Cd2Os2O7
452 2019-12-13 13:00  #2501, E6-2  Computational Material Designs: Current Status and Future Directions file
451 2018-04-06 10:00  #2502, E6  Entanglement and thermalization in many-body systems: recent progress file
450 2019-06-27 14:00  #2502, E6-2  Gapless Kitaev Spin Liquid to Loop and String Gases file
449 2019-09-10 15:00  #2502, E6-2  (2+1) D Duality Web from 3D Euclidean Lattice file
448 2019-11-20 16:00  #5302, E6-2  Correlation between superconducting transition temperature and critical current density in irradiated iron-based superconductors file
447 2019-02-21 16:00  #5313, E6-2  B-meson charged current anomalies - Theoretical status file
446 2017-11-08 13:00  #5318 (E6-2. 5th fl.)  “Emergent exotic quasiparticles in quantum spin liquids” file
445 2016-11-18 10:30  #5318(5th fl.)  Non-equilibrium many-body spin dynamics in diamond
444 2017-08-31 14:00  #5318(E6-2. 5th fl.)  “Berry phase and nonlinear response: photocurrent in noncentrosymmetric insulators and Weyl semimetals” file
443 2019-05-21 16:00  #5318, E6-2  Classification of flat bands according to the band-crossing singularity of Bloch wave functions file
442 2019-12-27 15:00  #5318, E6-2  The superconducting order parameter puzzle of Sr2RuO4 file
441 2018-02-12 15:00  #C303, (Creation Hall 3F, KAIST Munji Campus)  The recent result of XMASS Experiment
440 2020-10-15 16:00  (https://kaist.zoom.us/j/93997220310)  Towards resource-efficient and fault-tolerant quantum computation with nonclassical light