Fermionic Heisenberg glasses with BCS pairing interaction (original) (raw)

We have analyzed a fermionic infinite-ranged quantum Heisenberg spin glass with BCS coupling in real space in the presence of a magnetic field. It has been possible to locate the transition line between the normal paramagnetic phase (NP) and the phase where there is a long range order corresponding to pair formation in sites (PAIR). The nature of the transition line is also investigated. This transition ends at T f , the transition temperature between NP and spin glass phase (SG) where the static approximation and replica symmetry ansatz are reliable.