### Abstract

The thermodynamic properties of the high-pressure superconducting phase in CaLi _{2} have been studied. A pressure value of 45 GPa has been chosen, at which the critical temperature reaches the maximum (T _{C} = 12.9 K). The following results have been obtained. (i) The critical temperature cannot be calculated using the classical analytical formulas (McMillan or Allen-Dynes). (ii) The critical value of the Coulomb pseudopotential is high: μ ^{*} _{C} = 0.23. Generalizing the results, the function μ ^{*} _{C} (p) has a high value (μ ^{*} _{C} (p) > 0. 15) in practically the entire pressure range from 28 to 60 GPa. (iii) The remaining fundamental thermodynamic parameters differ from the Bardeen, Cooper, and Schrieffer (BCS) values. In particular, the zero-temperature energy gap to the critical temperature: R _{1} ≡ 2Δ (0)/k _{B}T _{C} = 3.95; the ratio of the specific heat for superconducting (C ^{S}) and the normal (C ^{N}) state: R _{2} ≡ (C ^{S} (T _{C}) - C ^{N} (T _{C})/C ^{N} (T _{C}) = 2.01; and the parameter connected with the zero-temperature thermodynamic critical field: R _{3} = T _{C}C ^{N} (T _{C})/H _{C} ^{2} (0) = 0.158. Finally, it has been shown that the value of the electronic effective mass is high: m ^{*}/m _{e} > 2.

Original language | English |
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Pages (from-to) | 779-783 |

Number of pages | 5 |

Journal | Solid State Communications |

Volume | 152 |

Issue number | 9 |

DOIs | |

Publication status | Published - May 2012 |

Externally published | Yes |

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### Keywords

- Cali -superconductor
- High-pressure effects
- Thermodynamic properties

### ASJC Scopus subject areas

- Condensed Matter Physics
- Chemistry(all)
- Materials Chemistry

### Cite this

_{2}at 45 GPa.

*Solid State Communications*,

*152*(9), 779-783. https://doi.org/10.1016/j.ssc.2012.01.045