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SEQUENCE:0
UID:UW-Physics-Event-3179
DTSTART:20140509T203000Z
DURATION:PT1H0M0S
DTSTAMP:20260419T175642Z
LAST-MODIFIED:20140430T172426Z
LOCATION:2241 Chamberlin Hall (coffee at 4:30 pm)
SUMMARY:“Phun” with Photoelectrons - or - What Sets the Tc in Cupr
 ate High-Temperature Superconductors?\, Physics Department Colloquium\
 , Dan Dessau\, University of Colorado-Boulder
DESCRIPTION:Angle-resolved photoemission spectroscopy (ARPES) has rece
 ntly emerged as one of the most powerful probes of the electronic stru
 cture of a solid\, directly giving the detailed energy-momentum disper
 sion relations (band structures)\, Fermi surfaces\, etc. – propertie
 s that are the starting point for almost all analyses of the physical 
 properties of a solid. Going more deeply\, ARPES also has unique abili
 ties to uncover the dynamical interaction effects or “self energies�
 �� that dominate the physical properties of correlated electron materi
 als.  <br>
\n<br>
\nPerhaps the most famous and exotic of correlated e
 lectron materials are high-temperature cuprate superconductors\, which
  have exotic “normal” and superconducting states\, neither of whic
 h are understood. Here I show our latest results on this problem\, foc
 using not just on the pairing energy scale (the gap Δ) but also the p
 air-breaking energy scale Γ. In contrast to conventional superconduct
 ors in which the superconducting transition temperature Tc is set by t
 he pairing energy alone\, I show that Tc in the cuprates is set by a c
 rossover between the pairing and pair-breaking energy scales\, each of
  which is strongly temperature-dependent. I then discuss how this is l
 ikely related to the strong interactions present in the normal state\,
  with many of these interactions “undressing” as the material goes
  superconducting.  <br>
\n
URL:https://www.physics.wisc.edu/events/?id=3179
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