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arXiv · 1308.1880

Weak Coupling BCS-like Superconductivity in the Pnictide Oxide Ba$_{1-x}$Na$_x$Ti$_2$Sb$_2$O (x=0 and 0.15)

Melissa Gooch·Phuong Doan·Zhongjia Tang·Bernd Lorenz·Arnold M. Guloy·Paul. C. W. Chu
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Abstract

We report the results of low-temperature heat capacity measurements of the pnictide oxide superconductor BaTi$_2$Sb$_2$O doped with sodium. The temperature and field dependent heat capacity data are well described by a single-gap BCS theory. The estimated values for the normal state Sommerfeld constant, the heat capacity jump at $T_c$, and the electron-phonon coupling constant are in favor of a conventional weak coupling superconductivity mediated by electron-phonon interaction. The results are discussed with regard to and compared with recent first principle calculations.

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Melissa Gooch, Phuong Doan, Zhongjia Tang, Bernd Lorenz, Arnold M. Guloy, Paul. C. W. Chu. 2013-08-08. Weak Coupling BCS-like Superconductivity in the Pnictide Oxide Ba$_{1-x}$Na$_x$Ti$_2$Sb$_2$O (x=0 and 0.15). https://doi.org/10.1103/physrevb.88.064510

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