Unusual behavior of superconductivity induced by anisotropic structure in the ferromagnetic state

¹ National Laboratory of Solid State Microstructures, Department of Physics Nanjing University - Nanjing 210093, PRC
² Chinese Center of Advanced Science and Technology (World Laboratory) P.O. Box 8730, Beijing 100080, PRC
³ Department of Physics, The Chinese University of Hong Kong - Hong Kong, PRC

Received: 10 September 2005
Accepted: 2 February 2006

Abstract

We find that the coexistence of ferromagnetism and superconductivity discovered recently can still be tolerated within the framework of the p-wave BCS-like mean-field theory if the structural anisotropy and the proper choice of the electronic occupation number are considered. Furthermore, only one type of electrons, in which the spin orientations are parallel to the direction of magnetization, can be paired in the general case. Thus the system keeps normal Fermi-liquid-like even at zero temperature, and it is supported by the experimental measurements on the specific heat.