visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
날짜 2020-11-20 14:30 
연사  
장소 Online 

 

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 연사 제목
공지 2025-02-24 16:00    2025년 봄학기 콜로키움 안내
공지 2025-02-27 16:00    2025년 봄 물리학과 특별세미나 (광학/응집물리 분야)
594 2015-07-16 16:00    Next-generation ultrafast laser technology for nonlinear optics and strong-field physics
593 2015-07-16 16:00    KAIST Physics Distinguished Lecture
592 2015-07-23 13:30    Enhanced ZnO based UV photonics and related applications file
591 2015-08-03 10:30    Axion Search
590 2015-08-04 11:00    Propagation of ultrasound through two- and three-dimensional strongly scattering media
589 2015-09-07 15:00    Advanced Optical Materials and Devices at NRL
588 2015-09-07 16:00    Physics Colloquium : 2015 Fall file
587 2015-09-14 14:00    Ultrafast X-ray Studies on Dynamics Matter in Extreme Conditions
586 2015-09-15 16:00    Physics Colloquium : 2014 Fall file
585 2015-10-14 18:00    인터스텔라 영화 속의 물리 file
584 2015-10-15 10:00    Development of Large-Bore, High Field Magnets at the NHMFL
583 2015-10-16 15:00    High Magnetic Fields to Probe the sub-eV range of Particle/Astroparticle Physics - From the OSQAR experiments at CERN up to new perspectives at LNCMI-Grenoble
582 2015-10-16 16:00    Fluctuations of entropy production in partially masked electric circuits
581 2015-10-23 10:30    How to write a good scientific paper[Open lecture series]
580 2015-10-23 15:00    Development of a Rogowski Coil as a new beam position monitor
579 2015-11-06 16:30    Topological Dirac line nodes in centrosymmetric semimetals
578 2015-11-10 16:00    Rapid heating of matter using high power lasers
577 2015-11-19 16:00    Emergent Collective Phenomena and Functions at Reduced Dimensions
576 2015-11-23 13:30    What's Beyond the Standard Model? Lessons from Run I and what might come in Run II
575 2015-11-24 16:00    Topology-based understanding of spin dynamics in inhomogeneously magnetized systems