visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
장소 E6-2, #1323 
일시 2015/12/11, 3:45PM 
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 일시 장소 연사 제목
108 Sep. 22 (Fri.), 02:30 PM  E6-2. 1st fl. #1323  Dr. GilHo Lee / Department of Physics, POSTECH  Quantum Electronic Transport in Graphene Hybrid Nanostructures file
107 Mar. 29 (Fri.), 04:00 PM  E6-2. 1st fl. #1323  Dr. Taeyoung Choi  Coherent Quantum Control and Magnetism on atoms – Trapped ion and ESR STM file
106 Dec. 26 (Wed.), 04:00 PM  E6-2. 1st fl. #1323  Dr. Isaac H. Kim  Brane-like defect in 3D toric code file
105 Apr. 19 (Fri.), 04:00 PM  E6-2. 1st fl. #1323  Dr. Seok Kyun Son  Graphene and hBN heterostructures file
104 Apr. 19 (Fri.), 02:30 PM  E6-2. 1st fl. #1323  Dr. YoungWoo Nam  A family of finite-temperature electronic phase transitions in graphene multilayers file
103 Apr. 01 (Fri.) 2:30 PM  E6-2. 1st fl. #1501  Dr. KICHEON KANG, Chonnam National University  Interference of single charged particles without a loop and dynamic nonlocality
102 Apr. 01 (Fri.) 4:15 PM  E6-2. 1st fl. #1501  Dr. JONG SOO LIM, KIAS  Cotunneling drag effect in Coulomb-coupled quantum dots
101 2016/03/11 4 PM  E6-2. 1st fl. #1501  Dr. Tae-Hwan KIM (POSTECH)  Jan. Switching handedness of of chiral solitons in Z4 topological insulators
100 Apr. 08 (Fri.), 13:30 PM  E6-2. 1st fl. #1501  Dr. Yunkyu Bang, Chonnam National Univ.  Theoretical Overview of Iron-based superconductors and its future
99 2016/03/11 1:30 PM  E6-2. 1st fl. #1501  Dr. Kwon Park  Topological phases of matter in nonequilibrium: Topology of the Wannier-Stark ladder
98 2015/10/16, 4PM  E6-2. 2nd fl. #2501  Prof. Yung-Fu Chen(Solid-state Laser Physics Laboratory,National Central University)  Fluctuations of entropy production in partially masked electric circuits
97 Jan.9 (Wed.), 04:00 PM  E6-2. 2nd fl. #2501  Dr. Heung-Sik Kim  Molecular Mott state in the deficient spinel GaV4S8 file
96 2015/09/14, 2PM  E6-2. 2nd fl. #2501  Dr. Hae Ja Lee ( Stanford University, SLAC )  Ultrafast X-ray Studies on Dynamics Matter in Extreme Conditions
95 Jun. 18 (MON), 10:00 AM  E6-2. 2nd fl. #2502  Dr. Thibault VOGT  Rydberg electromagnetically induced transparency and microwave-to-optical conversion using Rydberg atoms file
94 NOV. 23 (Fri), 03:00 PM  E6-2. 2st fl. #2501  Prof. Sang-Jin Sin  Entanglement string and Spin Liquid with Holographic duality file
93 MAR. 26 (TUE), 0300 PM  E6-2. 2st fl. #2501  Prof. Jung Hoon Han  Consideration of thermal Hall effect in frustrated and un-frustrated quantum magnets file
92 JAN. 7 (Mon), 03:00 PM  E6-2. 2st fl. #2501  Dr. Byoung min Kang  Many-Body Invariants for Multipoles in Higher-Order Topological Insulators file
91 Sep. 4 (Tue), 02:30 PM  E6-2. 2st fl. #2502  Dr. Changmin Lee, MIT  Ultrafast time- and angle-resolved photoemission spectroscopy (tr-ARPES) with extreme ultraviolet laser pulses file
90 May. 3 (Fri), 11:00 AM  E6-2. 2st fl. #2502  Prof. Changhee Sohn  Exotic Magnetism file
89 Apr. 08 (Fri.), 4:00 PM  E6-2. 5st fl. #1501  Dr. Changyoung Kim, SEOUL NATIONAL UNIV.  Spectroscopic studies of iron-based superconductors : what have we learned?