Phase Diagram, d-Wave Superconductivity, and Pseudogap of the t-t'-J Model at Finite Temperature

Abstract

Recently, robust d-wave superconductive (SC) order has been unveiled in the ground state of the 2D t− t0 − J model—with both nearest-neighbor (t) and next-nearest-neighbor (t0) hoppings—by density matrix renormalization group studies. However, there is currently a debate on whether the d-wave SC holds up strong on both t0=t > 0 and t0=t < 0 cases for the t− t0 − J model, which correspond to the electron- and hole-doped sides of the cuprate phase diagram, respectively. Here, we exploit state-of-the-art thermal tensor network approach to accurately obtain the phase diagram of the t− t0 − J model on cylinders with widths up to W¼ 6 and down to low temperature as T=J ≃ 0.06, pushing the boundaries of contemporary finite-T calculations. For t0=t > 0, we find a domelike SC regime with a diverging d-wave pairing susceptibility, χSC ∝ 1=Tα below a characteristic temperature Tc. Near optimal doping, Tc reaches its highest value of about 0.15J. Above Tc yet below a higher crossover temperature T , the magnetic susceptibility becomes suppressed, which can be related to the onset of pseudogap (PG) behaviors. On the other hand, for t0=t < 0, we find the pairing correlations are much weaker, although there exhibits a node-antinode structure in the PG regime as observed in the hole-doped cuprates. The thermal tensor network calculations of the t− t0 − J model underscore both the similarities and differences in the finite-temperature phase diagram between the fundamental model and cuprates, yielding unique insights into their intricate behaviors.

Publication
Phys. Rev. Lett.