= Fermionic Bogoliubov quasiparticle
{title2=$E_{\mathbf k}=\sqrt{\xi_{\mathbf k}^2+|\Delta|^2}$}
A fermionic excitation obtained by a canonical particle–hole <Bogoliubov transformation> of a paired mean-field Hamiltonian. The uniform spin-singlet problem has the displayed positive energy and weights $|u|^2=(1+\xi/E)/2$, $|v|^2=(1-\xi/E)/2$. It interpolates between particle-like and hole-like excitations across the Fermi surface. These single-particle excitations differ from collective phase and amplitude modes of the <order parameter>.
Back to article page
