摘要

We examine the two-dimensional t-J model by using variational approach combined with well established quantum Monte Carlo techniques [S. Sorella et al., Phys. Rev. Lett. 88, 117002 (2002)] that are used to improve systematically the accuracy of the variational ansatz. Contrary to recent density-matrix renormalization group and projected entangled-pair state calculations [P. Corboz et al., Phys. Rev. B 84, 041108(R) (2011)], a uniform phase is found for J/t = 0.4, even when the calculation is biased with an ansatz that explicitly contains stripe order. Moreover, in the small hole doping regime, that is, delta less than or similar to 0.1, our results support the coexistence of antiferromagnetism and superconductivity.

  • 出版日期2012-2-28