講演者： Daniel Braithwaite氏(SPSMS/LCP, CEA/Grenoble)
日時： １１月　２０日（木）　午後４時３０分から
場所： 青山学院大学　理工学部（相模原キャンパス）Ｌ棟６階　Ｌ６０３室

題目： 「Spin ladders and other low dimensional superconductors
AC calorimetry and resistivity measurements under pressure」


要旨：
The Sr1-xCaxCu24O41 system was the first spin ladder system to show
superconductivity. Whether the coupling is really due to the on
ladder pairing mechanism which was suggested is still an open
question. More detailed characterisation of the superconducting phase
is necessary. A first step was the measurement of the upper critical
field. Further results were obtained using a novel high pressure A.C.
calorimetry technique : The feasibility of detecting a jump in the
specific heat of a sample under pressure in a diamond anvil cell by
applying an a.c. power and measuring the temperature oscillations of
the sample was demonstrated 3 years ago by of A. Demuer in his PhD
thesis. Since then our aim has been to improve the technique and
better understand what is possible and what is not. I will review the
technique and our results on the spin ladder system, showing the
co-existence of superconductivity and AF order.
I will also present some results on the AV6O15 family where
superconductivity has also been found.

---------------------------------
共催：　青山学院大学　２１世紀COEプログラム