Magnetic breakdown and quantum oscillations in electron-doped high temperature superconductor $\mathrm{Nd_{2-x}Ce_{x}CuO_{4}}$

Abstract

Recent more precise experiments have revealed both a slow and a fast quantum oscillation in the c-axis resistivity of nearly optimal to overdoped electron-doped high temperature superconductor $\mathrm{Nd_{2-x}Ce_{x}CuO_{4}}$. Here we study this problem from the perspective of Fermi surface reconstruction using an exact transfer matrix method and the Pichard-Landauer formula. In this method, neither quasiclassical approximations for magnetic breakdown, nor {\em ad ho}c broadening of Landau levels, are necessary to study the high field quantum oscillations. The underlying Hamiltonian is a mean field Hamiltonian that incorporates a two-fold commensurate Fermi surface reconsruction. While the specific mean field considered is the $d$-density wave, similar results can also be obtained by a model of a spin density wave, as was explicitly demonstrated earlier. The results are consistent with an interplay of magnetic breakdown across small gaps in the reconstructed Fermi surface and Shubnikov-de Haas oscillations.