Gap symmetry of the heavy fermion superconductor CeCu$_2$Si$_2$ at ambient pressure
Autor: | Li, Yu, Liu, Min, Fu, Zhaoming, Chen, Xiangrong, Yang, Fan, Yang, Yi-feng |
---|---|
Rok vydání: | 2018 |
Předmět: | |
Zdroj: | Phys. Rev. Lett. 120, 217001 (2018) |
Druh dokumentu: | Working Paper |
DOI: | 10.1103/PhysRevLett.120.217001 |
Popis: | Recent observations of two nodeless gaps in superconducting CeCu$_2$Si$_2$ have raised intensive debates on its exact gap symmetry, while a satisfactory theoretical basis is still lacking. Here we propose a phenomenological approach to calculate the superconducting gap functions, taking into consideration both the realistic Fermi surface topology and the intra- and interband quantum critical scatterings. Our calculations yield a nodeless $s^\pm$-wave solution in the presence of strong interband pairing interaction, in good agreement with experiments. This provides a possible basis for understanding the superconducting gap symmetry of CeCu$_2$Si$_2$ at ambient pressure and indicates the potential importance of multiple Fermi surfaces and interband pairing interaction in understanding heavy fermion superconductivity. Comment: 7 pages, 5 figures |
Databáze: | arXiv |
Externí odkaz: |