Journal of Physics A Mathematical and General
Generalized Bogolyubov transformation
Fan Hong-Yi, Jack Vanderlinde
Abstract
The Bogolyubov transformation (1958) frequently used in dealing with pairing interactions of fermions, is extended to allow for binary coupling between any (even) number of fermions by using a matrix transformation 'coefficient'. The corresponding quasiparticles and quasi-vacuum state are derived. The normally ordered expansion of the unitary generalized Bogolyubov operator is obtained by application of the technique of integration within an ordered product (IWOP) for the fermion system.