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arXiv · 1511.00842

Thermodynamic properties in triangular-lattice superconductors

Xixiao Ma·Ling Qin·Huaisong Zhao·Yu Lan·Shiping Feng
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Abstract

The study of superconductivity arising from doping a Mott insulator has become a central issue in the area of superconductivity. Within the framework of the kinetic-energy-driven superconducting mechanism, we discuss the thermodynamic properties in triangular-lattice superconductors. It is shown that a sharp peak in the specific-heat appears at the superconducting transition temperature Tc, and then the specific-heat varies exponentially as a function of temperature for the temperatures T<Tc due to the absence of the d-wave gap nodes at the charge-carrier Fermi surface. In particular, the upper critical field follows qualitatively the charge-carrier pair gap type temperature dependence, and has the same dome-shaped doping dependence as Tc.

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Xixiao Ma, Ling Qin, Huaisong Zhao, Yu Lan, Shiping Feng. 2016-01-19. Thermodynamic properties in triangular-lattice superconductors. https://doi.org/10.1007/s10909-016-1521-0

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