Anisotropic Latent Heat of Vortex-Lattice Melting in Untwinned YBa{sub 2}Cu{sub 3}O{sub 7-{delta}}

Journal Article · Sun Jun 01 04:00:00 EDT 1997 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.78.4833· OSTI ID:531869

Schilling, A; Fisher, R A; Phillips, N E ^[1]; Welp, U; Kwok, W K; Crabtree, G W ^[2]

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1. Lawrence Berkeley National Laboratory and Department of Chemistry, University of California, Berkeley, California 94720 (United States)
2. Science and Technology Center for Superconductivity, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

We report a distinct thermal signature of the first-order vortex-lattice melting for the external magnetic field H both parallel and perpendicular to the c axis of an untwinned YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} single crystal. Latent heats and discontinuities in specific heat were observed for each configuration. The entropies of melting and the melting lines H{sub m}(T) both scale with an anisotropy parameter {gamma}{approx}8 . The specific heat of the vortex fluid is considerably larger than that of the vortex solid (by up to 2mJ/moleK{sup 2} ), which is not explained by simple arguments based on counting the numbers of thermodynamic degrees of freedom. {copyright} {ital 1997} {ital The American Physical Society}

• Research Organization: Lawrence Berkeley National Laboratory
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 531869
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 25 Vol. 78; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BARIUM OXIDES
COPPER OXIDES
ENTROPY
HIGH-TC SUPERCONDUCTORS
MAGNETIC FLUX
MELTING
SPECIFIC HEAT
VORTICES
YTTRIUM OXIDES