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arXiv · 1002.3355

Specific Heat vs Field in the 30 K Superconductor BaFe2(As0.7P0.3)2

J. S. Kim·P. J. Hirschfeld·G. R. Stewart·S. Kasahara·T. Shibauchi·T. Terashima·Y. Matsuda
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Abstract

We report specific heat measurements on the Fe-based superconductor BaFe2(As0.7P0.3)2, a material on which previous penetration depth, NMR, and thermal conductivity measurements have observed a high density of low-energy excitations, which have been interpreted in terms of order parameter nodes. Within the resolution of our measurements, the low temperature limiting C/T is found to be linear in field, i.e. we find no evidence for a Volovik effect associated with nodal quasiparticles in either the clean or dirty limit. We discuss possible reasons for this apparent contradiction.

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J. S. Kim, P. J. Hirschfeld, G. R. Stewart, S. Kasahara, T. Shibauchi, T. Terashima, Y. Matsuda. 2010-02-17. Specific Heat vs Field in the 30 K Superconductor BaFe2(As0.7P0.3)2. https://doi.org/10.1103/physrevb.81.214507

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