High Temperature Superconductivity in a Lightly Doped Quantum Spin Liquid

We have performed density-matrix renormalization group studies of a square lattice t-J model with small hole doping, delta << 1, on long four and six-leg cylinders. We include frustration in the form of a secondneighbor exchange coupling, J(2) = J(1)/2, such that the undoped (delta = 0) parent state is a quantum spin liquid. In contrast to the relatively short range superconducting (SC) correlations that have been observed in recent studies of the six-leg cylinder in the absence of frustration, we find power-law SC correlations with a Luttinger exponent, K-SC approximate to 1, consistent with a strongly diverging SC susceptibility, chi similar to T-(2-KSC) as the temperature T -> 0. The spin-spin correlations-as in the undoped state-fall exponentially suggesting that the SC pairing correlations evolve smoothly from the insulating parent state.

Automated summary

In a t-J model with small hole doping and frustration, power-law superconducting correlations and exponentially decreasing spin-spin correlations were observed, suggesting a smooth evolution from the insulating parent state. The presence of frustration led to a strong diverging superconducting susceptibility as the temperature approached zero.