Topological Superconductivity in the Doped Chiral Spin Liquid on the Triangular Lattice

It has long been proposed that doping a chiral spin liquid (CSL) or fractional quantum Hall state can give rise to topological superconductivity. Despite intensive effort, definitive evidences still remain lacking. We address this problem by studying the t-J model supplemented by time-reversal symmetry breaking chiral interaction J(chi) on the triangular lattice using density-matrix renormalization group with a finite concentration delta of doped holes. It has been established that the undoped, i.e., delta = 0, system has a CSL ground state in the parameter region 0.32 <= J(chi)/J <= 0.56. Upon light doping, we find that the ground state of the system is consistent with a Luther-Emery liquid with power-law superconducting and charge-density-wave correlations but short-range spin-spin correlations. In particular, the superconducting correlations, whose pairing symmetry is consistent with d +/- id wave, are dominant at all hole doping concentrations. Our results provide direct evidences that doping the CSL on the triangular lattice can naturally give rise to topological superconductivity.