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
246 2023-07-11 11:00  E6-2, #1323  Ordered phases, non-Fermi liquid, and quantum criticality driven by entanglement between multipoles and conduction electrons
245 2023-07-10 16:00  E6, #1323  Electronic structures of magnetic and non-magnetic ordering in d- and f-electrons systems
244 2019-07-10 16:00  Academic Cltural Complex (E9) 5층 스카이라운지  Public Lectures file
243 2016-07-28 16:00  #1323(E6-2. 1st fl.)  Low Dimensional Electrons: On the Road to Hybrid Quantum Systems
242 2022-07-14 15:00  E6 #1501 & Zoom  Pure two-dimensional quantum electron liquid and its phase transition
241 2022-07-14 14:15  E6 #1501 & Zoom  Hund and electronic correlations in ruthenium-based systems
240 2022-07-14 13:30  E6 #1501 & Zoom  Electronic structure and anomalous transport properties of topological materials by first principle calculation
239 2016-07-08 14:00  #1323(E6-2. 1st fl.)  Electronic quasiparticles in the quantum dimer model
238 2016-07-08 11:00  #1323(E6-2. 1st fl.)  Isostatic magnetism
237 2016-07-07 14:00  #1323(E6-2. 1st fl.)  Let there be topological superconductors
236 2019-07-03 15:00  E6-2, 2501  Many-body quantum electrodynamis (QED) with atoms and photons: A new platform for quantum optics" file
235 2023-07-14 11:00  E6-2 #1501  Interfaces engineering of thin film oxides
234 2019-01-23 16:00  Rm. C303, Creation Hall (3F), Munji Campus  Ultrasensitive Microwave Bolometer: Opportunity for Axion Detectors file
233 2020-01-17 16:00  #1323, E6-2  Symmetry Breaking and Topology in Superfluid 3He file
232 2019-01-09 16:00  E6-2. 2nd fl. #2501  Molecular Mott state in the deficient spinel GaV4S8 file
231 2021-01-28 18:00  Online Seminar  Quantum metamaterials: concept, theory, prototypes and possible applications file
230 2021-01-28 15:00  Zoom  Topological Transport of Deconfined Hedgehogs in Magnets file
229 2024-01-16 14:00  E6-2, #1323  Dimer Physics and Superconductivity in La3Ni2O7
228 2019-01-07 15:00  E6-2. 2st fl. #2501  Many-Body Invariants for Multipoles in Higher-Order Topological Insulators file
227 2022-01-26 13:00  E6 #1501  An Introduction to Cohomology groups file