visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
날짜 2015-12-11 15:45 
일시 2015/12/11, 3:45PM 
장소 E6-2, #1323 
연사 Dr. Ji Hun Sim (POSTECH) 

Dynamical mean field theory studies on heavy fermion system

 

Dec. 11 (Fri.), 15:45 PM, E6-2. 1st fl. #1323
Dr. Ji Hun Sim, POSTECH

 

 In f electron-based heavy fermion compounds, the temperature dependent behavior of the f electron is determined by the competition between Kondo effect and RKKY interaction. The f electron's magnetic moments bind to the itinerant quasiparticles to form composite heavy quasiparticle bands at low temperature to produce a large Fermi surface. When the f electrons are localized free moments, a small Fermi surface is induced with the absence of coherent contribution from f electrons. In the dynamical mean field theory approach of Ce-based heavy fermion compounds, we addressed that the Fermi surface sizes and their effective masses show continuous logarithmic scaling behavior (~ ln(T0/T)) with different characteristic temperatures.[1,2] Under the pressure or chemical doping, the temperature scale can be changed which is related to the movement of the quantum critical point.[3,4] Also, the role of crystalline electric field (CEF) to the spectral function has been investigated in YbRh2Si2 with well-defined CEF splitting. We describe the CEF multiplet Kondo resonance peaks similar to recent experimental observation [5] and suggest that the CEF effect enhances the localization of the Yb ions under pressure.[6] We will also discuss the temperature evolution of Kondo resonance band observed in topological Kondo insulator such as SmB6 and YbB6.[7]

 

References 
[1] H. C. Choi et al, Phys. Rev. Lett., 108, 016402 (2012).
[2] H. C. Choi et al, Phys. Rev. B, 88, 125111 (2013). 
[3] J. H. Shim et al, Science 318, 1615 (2007).
[4] S. Seo et al, Nat. Commun. 6, 6433 (2015).
[5] S. Ernst et al., Nature (London) 474, 362 (2011).
[6] O. Trovarelli et al., Phys. Rev. Lett. 85, 626 (2000).
[7] J. Denlinger et al., arXiv:1312.6637

 

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

 

번호 날짜 장소 제목
533 2024-04-19 15:00  E6-1, #1501  Engineering Physics for Semiconductor Equipment Innovation file
532 2024-04-11 16:00  E6-2, Rm#1323  Theoretical Studies of the Electric Field Induced Thermal Hall Effect in the Quantum Dimer Magnets XCuCl3 (X = Tl, K)
531 2024-03-28 11:00  E6, #2501  Geometric characterization of thermoelectric performance of two-dimensional quadratic band-crossing semimetals
530 2024-03-27 16:00  E6-2, #2502  [High Energy Theory Seminar] The Callan Rubakov Effect
529 2024-03-20 16:00  E6-2 #2502  [High-Energy Theory Seminar] Black hole states at finite N
528 2024-03-13 16:00  E6-2 #2502  [High-Energy Theory Seminar] The Schwarzschild Black Hole from Perturbation Theory to all Orders
527 2024-03-08 11:00  E6-2 #1323  2024 봄학기 광학분야 및 응집물리 특별세미나 전체 일정 file
526 2024-03-07 16:00  Zoom  [CAPP seminars] Development of Superconducting Transition Edge Sensors at SRON file
525 2024-02-26 16:00  E6-1 #1501  2024 봄학기 콜로키움 전체 일정 file
524 2024-02-16 10:00  E6, #1323  Optical conductivity of superconducting states driven by Van Hove singularities
523 2024-01-26 15:00  E6-2 #1323  In-situ 4D-STEM studies on surface reconstruction and polarization switching of perovskite oxides
522 2024-01-25 16:00  CAPP Seminar Room C303, Creation Hall, KAIST Munji Campus  [CAPP seminars] Detecting Gravitational Waves by Elecromagnetic Cavity
521 2024-01-24 15:00  E6-2 #1323  Determination of single molecule loading rate during mechanotransduction file
520 2024-01-16 16:00  E6-2, #2502  [High Energy Theory Seminar] Towards quantum black hole microstates
519 2024-01-16 14:00  E6-2, #1323  Dimer Physics and Superconductivity in La3Ni2O7
518 2024-01-03 11:00  E6-2, #1323  Interplay of Strong Correlations, Topology, and Disorder in 2D Quantum Matters
517 2023-12-19 16:00  E6-2, #1323  [High Energy Theory Seminar] Non-invertible symmetries, leptons, quarks, and why multiple generations
516 2023-12-14 16:00  CAPP Seminar Room C303, Creation Hall, KAIST Munji Campus  Superconducting qubits for large-scale quantum computers file
515 2023-12-08 10:30  E6-2, Rm#2502  Novel transport phenomena in insulators
514 2023-11-30 10:30  E6-2, #1322  [High-Energy Theory Seminar] 3d-3d correspondence and 2d N = (0,2) boundary conditions