BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Talks.cam//talks.cam.ac.uk//
X-WR-CALNAME:Talks.cam
BEGIN:VEVENT
SUMMARY:Charge-Density-Wave: Fermi-surface Reconstruction and Competing Or
 ders - Dr. Sven Friedemann
DTSTART:20191023T101500Z
DTEND:20191023T111500Z
UID:TALK133162@talks.cam.ac.uk
CONTACT:Malte Grosche
DESCRIPTION:Itinerant electrons are both very sensitive to and prone to ca
 use different ordered states. These include charge order like a charge-den
 sity-wave (CDW) state\, Mott metal-insulator transitions\, and superconduc
 tivity. Intriguingly\, these different ordered states arise from the same 
 fundamental interactions in metals. For instance\, in the presence of stro
 ng electron-phonon interaction\, superconductivity gaps out all conduction
  electrons. Similarly\, a combination of electron-phonon interaction and F
 ermi-surface nesting leads to CDW order with the gapping out of some elect
 ronic states. Thus\, both superconductivity and CDW order are linked to th
 e number of electrons involved and often also linked to the strength of th
 e same underlying interaction\, e.g. electron-phonon interaction. Conseque
 ntly\, one can expect a competition. However\, the modifications to the el
 ectronic structure and phonon spectrum of the CDW order may also give rise
  to promotion of superconductivity. Here\, I discuss recent results on the
  Fermi surface reconstruction as well as the interplay with as well as the
  interplay with superconductivity in NbSe2\, TiSe2\, and YBa2Cu3O7−δ.
LOCATION:Mott Seminar Room (531)\, Cavendish Laboratory\, Department of Ph
 ysics
END:VEVENT
END:VCALENDAR