Time-reversal symmetry breaking superconducting ground state in the doped Mott insulator on the honeycomb lattice

TL;DR

This paper theoretically predicts a time-reversal symmetry breaking superconducting state in doped Mott insulators on a honeycomb lattice, using advanced variational methods and benchmarks, revealing coexistence with antiferromagnetism at low doping.

Contribution

It introduces a novel theoretical discovery of a time-reversal symmetry breaking superconducting ground state in doped Mott insulators on honeycomb lattices, validated by multiple computational techniques.

Findings

Superconductivity coexists with antiferromagnetic order at low doping.

Consistent results between variational methods and exact diagonalization.

Identification of a time-reversal symmetry breaking superconducting phase.

Abstract

The emergence of superconductivity in doped Mott insulators has been debated for decades. In this paper, we report the theoretical discovery of a time-reversal symmetry breaking superconducting ground state in the doped Mott insulator (described by the well known t-J model) on honeycomb lattice, based on a recently developed variational method: the Grassmann tensor product state approach. As a benchmark, we use exact diagonalization and density-matrix renormalization methods to check our results on small clusters. We find systematic consistency for the ground-state energy as well as other physical quantities, such as the staggered magnetization. At low doping, the superconductivity coexists with antiferromagnetic ordering.