Noncoplanar magnetic orders and gapless chiral spin liquid on the kagome lattice with staggered scalar spin chirality

TL;DR

This paper investigates how staggered three-spin interactions influence magnetic orders and can stabilize a gapless chiral spin liquid with a spinon Fermi surface on the kagome lattice, revealing new quantum phases.

Contribution

It introduces a comprehensive study combining classical, mean-field, and variational methods to identify novel magnetic orders and a potential gapless chiral spin liquid in a kagome lattice model.

Findings

Identification of noncoplanar magnetic orders including interpolations between cuboc states

Discovery of a classically disordered region possibly hosting a gapless chiral spin liquid

Demonstration of competition-driven emergence of exotic ground states in frustrated spin systems

Abstract

Chiral three-spin interactions can suppress long-range magnetic order and stabilize quantum spin liquid states in frustrated lattices. We study a spin-1/2 model on the kagome lattice involving a staggered three-spin interaction $J_\chi$ in addition to Heisenberg exchange couplings $J_1$ on nearest-neighbor bonds and $J_d$ across the diagonals of the hexagons. We explore the phase diagram using a combination of a classical approach, parton mean-field theory, and variational Monte Carlo methods. We obtain a variety of noncoplanar magnetic orders, including a phase that interpolates between cuboc-1 and cuboc-2 states. In the regime of dominant $J_{\chi}$, we find a classically disordered region and argue that it may harbor a gapless chiral spin liquid with a spinon Fermi surface. Our results show that the competition between the staggered three-spin interaction and Heisenberg exchange interactions gives rise to unusual ground states of spin systems.