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Title: Magnetocaloric studies of the peak effect in Nb

Abstract

We report a magnetocaloric study of the peak effect and Bragg glass transition in a Nb single crystal. The thermomagnetic effects due to vortex flow into and out of the sample are measured. The magnetocaloric signature of the peak-effect anomaly is identified. It is found that the peak effect disappears in magnetocaloric measurements at fields significantly higher than those reported in previous ac-susceptometry measurements. Investigation of the superconducting-to-normal transition reveals that the disappearance of the bulk peak effect is related to inhomogeneity broadening of the superconducting transition. The emerging picture also explains the concurrent disappearance of the peak effect and surface superconductivity, which was reported previously in the sample under investigation. Based on our findings, we discuss the possibilities of multicriticality associated with the disappearance of the peak effect.

Authors:
; ; ; ;  [1]
  1. Department of Physics, Brown University, Providence, Rhode Island 02912 (United States)
Publication Date:
OSTI Identifier:
20957841
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 17; Other Information: DOI: 10.1103/PhysRevB.75.174519; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; GLASS; MAGNETIC SUSCEPTIBILITY; MONOCRYSTALS; NIOBIUM; PEAKS; SUPERCONDUCTIVITY; SURFACES; VORTEX FLOW

Citation Formats

Daniilidis, N. D., Dimitrov, I. K., Mitrovic, V. F., Elbaum, C., and Ling, X. S.. Magnetocaloric studies of the peak effect in Nb. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.174519.
Daniilidis, N. D., Dimitrov, I. K., Mitrovic, V. F., Elbaum, C., & Ling, X. S.. Magnetocaloric studies of the peak effect in Nb. United States. doi:10.1103/PHYSREVB.75.174519.
Daniilidis, N. D., Dimitrov, I. K., Mitrovic, V. F., Elbaum, C., and Ling, X. S.. Tue . "Magnetocaloric studies of the peak effect in Nb". United States. doi:10.1103/PHYSREVB.75.174519.
@article{osti_20957841,
title = {Magnetocaloric studies of the peak effect in Nb},
author = {Daniilidis, N. D. and Dimitrov, I. K. and Mitrovic, V. F. and Elbaum, C. and Ling, X. S.},
abstractNote = {We report a magnetocaloric study of the peak effect and Bragg glass transition in a Nb single crystal. The thermomagnetic effects due to vortex flow into and out of the sample are measured. The magnetocaloric signature of the peak-effect anomaly is identified. It is found that the peak effect disappears in magnetocaloric measurements at fields significantly higher than those reported in previous ac-susceptometry measurements. Investigation of the superconducting-to-normal transition reveals that the disappearance of the bulk peak effect is related to inhomogeneity broadening of the superconducting transition. The emerging picture also explains the concurrent disappearance of the peak effect and surface superconductivity, which was reported previously in the sample under investigation. Based on our findings, we discuss the possibilities of multicriticality associated with the disappearance of the peak effect.},
doi = {10.1103/PHYSREVB.75.174519},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 17,
volume = 75,
place = {United States},
year = {Tue May 01 00:00:00 EDT 2007},
month = {Tue May 01 00:00:00 EDT 2007}
}
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