visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
날짜 2023-06-08 16:00 
일시 June 8, 16:00 
장소 E6-2, #1323 
연사 Prof. Gun-Do Lee( Seoul National University) 
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 장소 제목
336 2018-10-04 16:00  #1323, E6-2  Engineering light absorption in an ultrathin semiconductor metafilm file
335 2018-10-11 16:00  #1323, E6-2  Dirac electrons in a graphene quasicrystal file
334 2018-10-12 14:30  E6-2. 1st fl. #1323  Quantum Advantage in Learning Parity with Noise file
333 2018-10-12 16:00  E6-2. 1st fl. #1323  Direct observation of a two-dimensional hole gas at oxide interfaces file
332 2018-10-15 16:00  #1323, E6-2  Universal properties of macroscopic current-carrying systems file
331 2018-10-16 10:00  #1323, E6-2  Capturing protein cluster dynamics and gene expression output in live cells file
330 2018-10-18 10:00  #1323, E6-2  Understanding membrane protein folding using single-molecule force techniques file
329 2018-10-18 16:00  #1323, E6-2  Applications of nonlinear optics for condensed matter researches file
328 2018-10-19 10:00  #1323, E6-2  Energy conversion processes during magnetic reconnection in a laboratory plasma file
327 2018-10-24 10:30  E6-1, Lecture Room 1501(1F)  Photonic integration of next-generation clocks and Hertz-absolute-accuarcy optical frequenncy synthesizers file
326 2018-10-25 16:00  #1323, E6-2  Abelian and non-Abelian dark photons file
325 2018-10-26 16:00  #1323, E6-2  Coexisting triple-point and nodal-line topological magnons and thermal Hall effect in pyrochlore iridates file
324 2018-11-01 16:00  #1323, E6-2  Direct holography from a single snapshot file
323 2018-11-08 16:00  #1323, E6-2  Conformality lost file
322 2018-11-09 14:30  E6-2. 1st fl. #1323  Moiré superlattices – from twisted bilayer graphene to quasicrystal file
321 2018-11-09 16:00  E6-2. 1st fl. #1323  Quantum sensing and imaging with diamond defect centers for nano-scale spin physics file
320 2018-11-21 15:00  #1323, E6-2  Engineering topological quantum physics at the atomic scale file
319 2018-11-22 15:00  E6 Room(#1323)  Experimental and Computational Study on Physical Properties based on Granular System file
318 2018-11-23 15:00  E6-2. 2st fl. #2501  Entanglement string and Spin Liquid with Holographic duality file
317 2018-11-29 16:00  #1323, E6-2  양자 칸델라 실현을 위한 단일 광자 발생장치 개발 file