Zusammenfassung
We report the theoretical discovery of a novel time reversal symmetry
breaking superconducting state in the t-J model on the honeycomb lattice, based
on a recently developed variational method - the Grassmann tensor product state
approach. As a benchmark, we use exact diagonalization (ED) and density matrix
renormalization (DMRG) methods to check our results on small clusters.
Remarkably, we find systematical consistency for the ground state energy as
well as other physical quantities, such as the staggered magnetization. At low
doping, the superconductivity coexists with anti-ferromagnetic ordering.
Nutzer