CALORIMETRIC TRANSITIONS ON THE MELTING LINE OF THE VORTEX SYSTEM AS A FUNCTION OF OXYGEN DEFICIENCY IN HIGH-PURITY YBA2CU3OX

Authors
ROULIN M JUNOD A ERB A WALKER E
Citation
M. Roulin et al., CALORIMETRIC TRANSITIONS ON THE MELTING LINE OF THE VORTEX SYSTEM AS A FUNCTION OF OXYGEN DEFICIENCY IN HIGH-PURITY YBA2CU3OX, Physical review letters, 80(8), 1998, pp. 1722-1725
Citations number
25
Categorie Soggetti
Physics
Journal title
Physical review letters → ACNP
ISSN journal
00319007
Volume
80
Issue
8
Year of publication
1998
Pages
1722 - 1725
Database
ISI
SICI code
0031-9007(1998)80:8<1722:CTOTML>2.0.ZU;2-1
Abstract
We report adiabatic specific heal measurements for a high-purity YBa2C u3Ox twinned single crystal. The order of the transition on the meltin g line of the vortex system B-m (T) is investigated for three oxygen c oncentrations. For x = 7.00, no critical end point is observed. For x = 6.94, first-order transitions give way to second-order transitions a bove a tricritical point at a field B-cr = 9.5 T, and the slope of B-m (T) changes. The latent heal, the slope of B-m(T), and B-cr increase w ith x. Data for less pure crystals are included for comparison purpose s. [S0031-9007(97)05280-0].