visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
날짜 2023-06-08 16:00 
연사  
장소 E6-2, #1323 
서울대학교 이건도 연구교수님을 모시고 'Thermal decoupling in high-Tc cuprate superconductors' 주제에 대한 세미나를 개최하고자 합니다. 
물리학과 구성원 여러분들의 많은 참여 부탁드립니다.
 
1) Time : at 16:00 on June 8, 2023 
2) Venue : Room 1323, KAIST Natural Sciences Lecture Hall(E6) (자연과학동 1323호)  
3) Speaker : 이건도 연구교수 (서울대학교) 
4) Talk Title
    - Thermal decoupling in high-Tc cuprate superconductors
 
5) Abstract
    -  Although many years have passed since the discovery of high-critical-temperature (high-Tc) superconducting materials, the underlying mechanism is still unknown. The B1g phonon anomaly in high-Tc cuprate superconductors has long been studied; however, the correlation between the B1g phonon anomaly and superconductivity has yet to be clarified. In the present study, we successfully reproduced the B1g phonon anomaly in YBa2Cu3O7 (YBCO) using an ab initio molecular dynamics (AIMD) simulation and temperature-dependent effective potential (TDEP) method. The Ag phonon by Ba atoms shows a more severe anomaly than the B1g phonon at low temperatures. Our analysis of the phonon anomaly and the temperature-dependent phonon dispersion indicated that decoupling between thermal phenomena and electron transport at low temperatures leads to layer-by-layer thermal decoupling in YBCO. Electronically and thermally isolated Ba atoms in YBCO are responsible for thermal decoupling which is found to be the origin of the breakdown of the Wiedemann-Franz law and the thermal Hall effect in cuprates. The analytic study of the thermal decoupling revealed that Planckian dissipation expressing linear-T resistivity is another expression of the Fermi liquid of the CuO2 plane. The Uemura plot of the relationship between Tc and the Fermi temperature, as well as the superconducting dome in YBCO, is explained rigorously and quantitatively. Our findings not only present a new paradigm for understanding high-Tc superconductivity but also imply that the spontaneous formation of low-temperature layers in materials can lead to revolutionary changes in the thermal issues of industrial fields.

 

[1] S. LeeW. ChoiY. KimY.-K. KwonD. SongM. KimG.-D. Lee Thermal decoupling in high-Tc cuprate superconductors, Preprint at https://arxiv.org/abs/2303.11600 (2023).

 
번호 날짜 연사 제목
476 2016-10-27 16:00    Terahertz Metal Optics
475 2016-11-01 14:30    Search for dark sector particles in the B-factory experiments
474 2016-11-04 13:30    Exotic phenomena at oxide LaAlO3/SrTiO3 hetero-interface and their applications
473 2016-11-04 15:00    Quantum information experiments using few electron spins in semiconductors
472 2016-11-1 10:30    Time scale dependent dynamics in InAs/InP quantum dot gain media
471 2016-11-10 16:00    Low Dimensional Active Plasmonics and Electron Optics in Graphene
470 2016-11-11 13:30    Bandgap Engineering of Black Phosphorus
469 2016-11-11 16:00    Dirac fermions in condensed matters
468 2016-11-16 16:00    Realizing Haldane Model in Fe-based Honeycomb Ferromagnetic Insulators
467 2016-11-18 10:30    Non-equilibrium many-body spin dynamics in diamond
466 2016-11-24 16:00    Harmonic oscillator physics with single atoms in a state-selective optical potential
465 2016-11-29 16:00    Symmetry Protected Kondo Metals and Their Phase Transitions
464 2016-12-09 13:30    Entanglement area law in strongly-correlated systems
463 2016-12-09 16:00    Shift Charge and Spin Photocurrents in Dirac Surface States of Topological Insulator
462 2016-12-12 13:30    “Possible symmetry in the phase diagrams of electron- & hole-doped cuprate high-Tc superconductors”
461 2016-12-8 16:00    Dynamical Resonance between Two Optical Cavities via Optomechanical Oscillator
460 2017-01-09 16:00    Topological Defects and Phase Transitions" file
459 2017-02-01 14:00    Quantum electron optics using flying electrons
458 2017-03-02 16:00    “Progress in the comparison of ARPES to DMFT for d and f strongly correlated electron systems”
457 2017-03-06 16:00    Spring 2017: Physics Colloquium file