visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
날짜 2020-11-20 14:30 
일시 Nov. 20 (Fri.), 02:30 PM 
장소 Online 
연사 Dr. Doohee Cho 

 

SRC Seminar

 

 

 

 

 

Lumpy Cooper pairs in an iron-based superconductor

 

 

 

Dr. Doohee Cho

 

Department of Physics, Yonsei University

 

 

 

Nov. 20 (Fri.), 02:30 PM

 

Online seminar

 

https://kaist.zoom.us/j/82243139535
회의 ID: 822 4313 9535
암호: 151742

 

 

 

 

 

 

 

Abstract:

 

Cooper pairs can tunnel through the vacuum barrier between two superconducting electrodes, known as a Josephson junction. One can extract the superconducting order parameter from the current-voltage curves close to zero bias. We use atomic-resolution Josephson scanning tunneling microscopy (STM) to visualize the spatial variations of the superfluid in the iron-based superconductor FeTe0.55Se0.45. To measure Cooper-pair tunneling, a Pb-coated tip was employed and its superconductivity was thoroughly verified by measuring noise enhancement induced by Andreev-reflection on Pb(111) surface. By simultaneously acquiring the topographic and electronic properties, we find that this inhomogeneity in the superfluid is not caused by structural disorder or strong inter-pocket scattering, and does not correlate with variations in the energy of the Cooper pair-breaking gap. Instead, we see a clear spatial correlation between superfluid density and the quasiparticle strength, defined as the height of the coherence peak, on a local scale. Our results shed light on the interplay between superconductivity and quasiparticle character that has been observed by photoemission experiments across the critical temperature in the unconventional superconductors.

 

 

 

 

 

Contact: SunYoung Choi, (sunyoungchoi@kaist.ac.kr)

Center for Quantum Coherence in Condensed Matter, KAIST

번호 날짜 장소 제목
356 2016-05-11 16:00  E6-2. #1323(1st fl.)  The quest for novel high-temperature superconductors---Prospects and progress in iridates
355 2016-10-07 16:00  E6-2. #1323(1st fl.)  “Tilt engineering of 4d and 5d transition metal oxides?”
354 2016-11-10 16:00  E6-2. #1323(1st fl.)  Low Dimensional Active Plasmonics and Electron Optics in Graphene
353 2016-11-04 13:30  E6-2. #1323(1st fl.)  Exotic phenomena at oxide LaAlO3/SrTiO3 hetero-interface and their applications
352 2016-05-24 16:00  E6-2. #1323(1st fl.)  Electronic and magnetic properties of 2D transition-metal thiophosphates and tunability of magnetic order with carrier density
351 2016-11-04 15:00  E6-2. #1323(1st fl.)  Quantum information experiments using few electron spins in semiconductors
350 2016-10-07 13:30  E6-2. #1323(1st fl.)  “Symmetry and topology in transition metal dichalcogenide?”
349 2022-05-12 16:00  E6-2. #1323 & Zoom  New frontiers of electroweak physics at the LHC
348 2022-05-18 16:00  E6-2. #1323 & Zoom  Geometry, Algebra, and Quantum Field Theory
347 2022-05-19 16:00  E6-2. #1323 & Zoom  Chasing Long Standing Neutrino Anomalies with MicroBooNE
346 2022-05-11 16:00  E6-2. #1323 & Zoom  Gravity as a phenomenon in quantum dynamics
345 2023-06-22 16:00  E6-2,1323  [High Energy Physics Seminar] The Branes Behind Generalized Symmetry Operators
344 2015-07-15 14:00  E6-2,1323  Electronic and optical properties of titanate-based oxide superlattices
343 2019-12-27 15:00  E6-2,#5318  The superconducting order parameter puzzle of Sr2RuO4 file
342 2023-11-08 10:00  E6-2,#2502 & zoom  [High Energy Theory seminar] The Vacuum Sector of Asymptotically Isometric Codes
341 2019-07-21 12:00  E6-2,# 5318  Challenges and Opportunities in Theoretical Particle Physics 2019 file
340 2023-10-11 16:00  E6-2, Rm2502  [High Energy Theory Seminar] Axion Magnetic Resonance
339 2023-12-08 10:30  E6-2, Rm#2502  Novel transport phenomena in insulators
338 2016-04-06 15:30  E6-2, RM #1323  Superconducting Quantum Interference Devices for Precision Detection
337 2017-12-15 09:20  E6-2, Lecture Room #1323  Workshop on Magnetism in Unconventional Superconductors 개최 file