Phase Diagram of the Triangular t-J Model with Multiple Spin Exchange in the Doped-Mott Region

TL;DR

This paper investigates the phase diagram of the triangular t-J model with multiple spin exchanges, revealing a spin-charge separation phase in doped Mott insulators, explaining experimental heat capacity features in monolayer liquid helium-3.

Contribution

It provides the first detailed analysis of the triangular t-J model with multiple spin exchanges using exact diagonalization, highlighting a novel spin-charge separation phase.

Findings

Identification of a spin-charge separation phase in the doped-Mott region.

Explanation of the double peaked heat capacity in monolayer liquid $^3$He.

Evidence of competition between ferromagnetic and antiferromagnetic exchanges.

Abstract

We study the triangular $t$-$J$ model with multiple spin exchange interactions using exact diagonalization of small clusters, as a model of monolayer liquid $^3$He. A phase where the energy spectrum suggest the behaviors of spin-charge separation is realized in the doped-Mott region due to the competition between ferromagnetic two-spin and antiferromagnetic four-spin exchange interactions. This behavior gives an interpretation of the double peaked heat capacity recently observed in monolayer liquid $^3$He adsorbed on a graphite.