Hole Density in Charge Stripes and Effect of Next-Nearest-Neighbor Transfer

Abstract

By applying a variational Monte Carlo method to the two-dimensional t-J model, a couple of properties of striped states are studied. In the charge domain walls vertical (or horizontal) to the lattice (VDW), the hole density $\rho \ell$ is favorable in energy similarly for 0.5 $\lesssim \rho \ell \lesssim 1$, whereas in the diagonal domain walls (DDW) the stable hole density is limited to $\rho \ell$ = 1. Negative next-nearest-neighbor transfer (t′/t < 0) further stabilizes VDW with $\rho \ell$ = 0.5 and DDW with $\rho \ell$ = 1 against the $d_{x^2 - y^2 }$-wave superconducting state.