BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Talks.cam//talks.cam.ac.uk//
X-WR-CALNAME:Talks.cam
BEGIN:VEVENT
SUMMARY:Understanding superconductivity in spin ladders: new tools and a h
 ard climb! - Daniel Braithwaite\, CEA Grenoble
DTSTART:20061122T111500Z
DTEND:20061122T121500Z
UID:TALK5909@talks.cam.ac.uk
CONTACT:Michael Sutherland
DESCRIPTION:The concept of spin ladders originally appeared as a toy for t
 heorists giving a simple model to study the interactions in the 2D Cu-O pl
 anes of high-T¬c superconductors. However due to some of the fascinating 
 properties predicted by the theoretical work\, and the fact that a growing
  number of materials showing a ladder structure have been synthesised\, th
 e study of ladder systems has evolved into a well established area of rese
 arch in its own right. The possibility of finding novel superconducting ph
 ases in these compounds was predicted quite early on. However despite the 
 discovery of superconductivity in the Sr0.4Ca13.6Cu24O41 system\, and more
  recently in the AV6O15 family\, relatively little experimental work has b
 een done and the nature of the superconducting state remains a mystery. Th
 is lack of data is mainly due to experimental difficulties\, as the superc
 onducting phases appear only at high pressure\, and the samples are extrem
 ely sensitive.  I will present our results on the measurements of the uppe
 r critical field\, and the phase diagram of the superconducting and anti-f
 erromagnetic phases\, as well as some other recent experimental and theore
 tical studies\, and discuss the implications for superconductivity. Clearl
 y we are still a long way from understanding these systems and the next st
 eps will require new experimental techniques. I will present a new experim
 ental development which allows pressurizing larger samples in a liquid med
 ium up to high enough pressures to study these systems\, and should allow 
 a new step forward.
LOCATION:Mott Seminar Room\, Cavendish Laboratory\, Department of Physics
END:VEVENT
END:VCALENDAR