Quantization ofthe quasiparticle spectrum in the mixed state of d-wavesuperconductors

Abstract

We have investigated the distinctive features of the band spectrum, eigenfunctions, and density of states (DOS) for low-lying quasiparticle excitations in the mixed state of clean d-wave superconductors (Hc1<<H<<Hc2). Our study is based on an approximate analytical solution of the Bogoliubov-de Gennes equations for quasiparticles with momenta close to gap node directions. Both the quantized energy spectrum and the spatially averaged residual DOS are shown to depend fundamentally on the vortex lattice geometry.