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VERSION:2.0
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METHOD:PUBLISH
BEGIN:VEVENT
DTSTAMP:20260818T225714Z
UID:https://www.mpsd.mpg.de/events/5460/17178
DTSTART:20160511T090000Z
DTEND:20160511T100000Z
CLASS:PUBLIC
CREATED:20160509T075827Z
DESCRIPTION:A characteristic of ferroic materials is the emergence of a tem
 porally static finite expectation value of an order parameter. Here\, we i
 ntroduce a new mechanism [1] for ferroic order\, in which a non-zero quasi
 -static magnetoelectric quadrupolar order appears\, mediated by a strong c
 oupling of spin and phonon fluctuations. We show that our proposed mechani
 sm is consistent\, to our knowledge\, with many experimental observations 
 for the onset of the pseudo-gap phase in cuprate superconductors and there
 fore propose the quasi-static magnetoelectric quadrupole as a possible pse
 udo-gap order parameter. By using first-principles calculations in combina
 tion with our recent developed formalism [2\,3]\, to calculate multipole m
 oments within a Berry phase approach\, we calculate the magnitude of the e
 ffect for the the prototypical cuprate superconductor\, HgBa2CuO4+δ. Usin
 g these results we finally show that our mechanism embraces several key fi
 ndings of experimental reports and in addition also aspects of previous th
 eoretical models.\nSpeaker: Michael Fechner
LAST-MODIFIED:20160510T080626Z
LOCATION:CFEL (Bldg. 99)\, Room: Seminar Room IV\, O1.111
ORGANIZER;CN=Andrea Cavalleri:mailto:
SUMMARY:MPSD Seminar: Parity odd magnetism and spin-phonon coupling in the 
 pseudo-gap phase of cuprate superconductors
URL;VALUE=URI:https://www.mpsd.mpg.de/events/5460/17178
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