Abstract
In this paper, we report the transport, thermodynamic, and superconducting properties of a new filled skutterudite synthesized under high pressure and high temperature. The electrical resistivity of 3.4–4., carrier concentration of 3.8–6., and positive Hall coefficient suggest that is a semimetal with hole carriers. An anomaly due to low-energy optical modes corresponding to an Einstein temperature of 150 K was observed in the specific heat. Resistivity, dc magnetic susceptibility, and specific heat measurements indicate bulk superconductivity below 2.5 K. The specific heat anomaly at , is in agreement with the Bardeen-Cooper-Schrieffer (BCS) value of 1.43. The electron-phonon coupling constant is estimated to be 0.47. is classified as a BCS-type, weakly coupled type-II superconductor with an upper critical field of kOe and Ginzburg-Landau coherence length of nm.
- Received 18 January 2018
- Revised 7 May 2018
DOI:https://doi.org/10.1103/PhysRevB.98.024513
©2018 American Physical Society