Spontaneous spin stripe dimerization in the doped t-J model

TL;DR

This study shows that doping in the extended t-J- model stabilizes spin dimerized stripe phases, which are unstable at zero doping, revealing a doping-dependent phase transition.

Contribution

The paper introduces an explicit spin dimerization parameter and demonstrates how doping stabilizes the dimerized stripe phase in the t-J model.

Findings

Dimerized spin liquid is unstable at  < 0.3 at zero doping.

Doping decreases the critical _c(x) for stability.

Dimerized phase remains stable at =0 for doping above x_c.

Abstract

To investigate spin dimerization in the t-J model we consider the extended t-J-\delta model with explicit spin dimerization introduced via parameter \delta. At zero doping the dimerized spin liquid is unstable at \delta < \delta_c = 0.3. We demonstrate that the doping stabilizes the dimerized stripe phase: the \delta_c(x) decreases when doping x increases. At doping larger than critical, x > x_c, the dimerized phase is stable even without explicit dimerization, i.e. at \delta=0.