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arXiv · 1308.2290

Heat Capacity of Single Crystal CuxTiSe2 Superconductors

J. Kacmarcik·Z. Pribulova·V. Paluchova·P. Szabo·P. Husanikova·G. Karapetrov·P. Samuely
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Abstract

We present heat capacity measurements on a series of superconducting Cu$_x$TiSe$_2$ single crystals with different Cu content down to 600 mK and up to 1 T performed by ac microcalorimetry. The samples cover a large portion of the phase diagram from an underdoped to a slightly overdoped region with an increasing superconducting critical temperature and the charge density wave (CDW) order gradually suppressed. The electronic heat capacity as a function of normalized temperature $T/T_c$ shows no difference regardless of the concentration of copper, i.e., regardless of how much the CDW order is developed in the samples. The data analysis reveals consistently a single s-wave gap with an intermediate coupling strength $2Δ/k_BT_c$ = 3.7 for all samples.

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J. Kacmarcik, Z. Pribulova, V. Paluchova, P. Szabo, P. Husanikova, G. Karapetrov, P. Samuely. 2013-08-10. Heat Capacity of Single Crystal CuxTiSe2 Superconductors. https://doi.org/10.1103/physrevb.88.020507

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