Usually, we define the momentum k-space Brillouin zone (by Fourier transformed from the real space x with a wavefunction ψ(x) to the momentum k-space) for:
(1) quadratic non-interacting (free) systems (such as those can be written in terms of BdG equation.)
and
(2) translational invariant systems (so one can define the conjugate momentum k as a good quantum number).
Question: Could we define the momentum k-space Brillouin zone for
non-quadratic and interacting systems
but translational invariant systems? (Namely can we modify (1) to interacting, but keep (2)?)
No comments:
Post a Comment