# Dirac Spin Liquid on the Spin-1/2 Triangular Heisenberg Antiferromagnet

## TL;DR

This study uses DMRG simulations with flux insertion to provide strong evidence that the spin-1/2 triangular Heisenberg antiferromagnet hosts a gapless U(1) Dirac spin liquid with characteristic excitations and universal entanglement properties.

## Contribution

It demonstrates the presence of a gapless U(1) Dirac spin liquid in the model using flux insertion and excitation spectrum analysis, advancing understanding of quantum spin liquids.

## Key findings

- Evidence for gapless U(1) Dirac spin liquid behavior.
- Observation of Dirac cone structures in excitation spectrum.
- Universal entanglement entropy response under flux insertion.

## Abstract

We study the spin liquid candidate of the spin-$1/2$ $J_1$-$J_2$ Heisenberg antiferromagnet on the triangular lattice by means of density matrix renormalization group (DMRG) simulations. By applying an external Aharonov-Bohm flux insertion in an infinitely long cylinder, we find unambiguous evidence for gapless $U(1)$ Dirac spin liquid behavior. The flux insertion overcomes the finite size restriction for energy gaps and clearly shows gapless behavior at the expected wave-vectors. Using the DMRG transfer matrix, the low-lying excitation spectrum can be extracted, which shows characteristic Dirac cone structures of both spinon-bilinear and monopole excitations. Finally, we confirm that the entanglement entropy follows the predicted universal response under the flux insertion.