Competing Spin Liquid States in the Spin-$1/2$ Heisenberg Model On Triangular Lattice

Understand

We study the spin-$1/2$ Heisenberg model on the triangular lattice with the antiferromagnetic first ($J_1$) and second ($J_2$) nearest-neighbor interactions using density matrix renormalization group.

• By studying the spin correlation function, we find a $120^{\circ}$ magnetic order phase for $J_2 \lesssim 0.07 J_1$ and a stripe antiferromagnetic phase for $J_2 \gtrsim 0.15 J_1$.
• Between these two phases, we identify a spin liquid region characterized by the exponential decaying spin and dimer correlations, as well as the large spin singlet and triplet excitation gaps on finite-size systems.
• We find two near degenerating ground states with distinct properties in two sectors, which indicates more than one spin liquid candidates in this region.