Generalization of the Hartree-Fock-Bogoliubov theory: one and two quasiparticle excitations

Details Generalization of the Hartree-Fock-Bogoliubov theory: one and two quasiparticle excitations Generalization of the Hartree-Fock-Bogoliubov theory: one and two quasiparticle excitations

2003-07-30

arxiv.org/abs/cond-mat/0307745v1

Physics

Condensed Matter

Soft Condensed Matter

27 pages, 3 figures

Scientific paper

We present a generalization of the Hartree-Fock Bogoliubov (HFB) theory in which the coupling between one and two quasi-particles is taken into account.This is done by writing the excitation operators as linear combinations of one and two HFB quasi-particles. The excitation energies and the quasi-particle amplitudes are given by generalized Bogoliubov equations. The excitation spectrum has two branches. The first one is a discrete branch which is gapless and has a phonon character at large wave-length and, contrarily to HFB, is always stable. This branch is detached from a continuum branch whose threshold, at fixed total momentum, coincides with the two quasi-particle threshold of the HFB theory. The gap between these two branches at P=0 is equal to two times the HFB gap, which then provides for the relevant energy scale. We also give numerical results for a specific case.

Affiliated with

Also associated with

No associations

Rating

Generalization of the Hartree-Fock-Bogoliubov theory: one and two quasiparticle excitations does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Generalization of the Hartree-Fock-Bogoliubov theory: one and two quasiparticle excitations, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Generalization of the Hartree-Fock-Bogoliubov theory: one and two quasiparticle excitations will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-662915