Interplay between pseudogap, Van Hove singularity and entropy maximum within the CDMFT phase diagram of the 2D Hubbard model

Recent experiments found that the pseudogap temperature T^* of hole-doped cuprates drops suddently at a critical doping where charge-carrier density exhibits a sharp change[1,2,3]. The sudden drop in T^* is accompanied by a nearly vertical line in the phase diagram where entropy is maximum [4]. Theoretical work studied the link between the change in electronic properties and the location of the Van Hove singularity[5,6]. We address this multi-faceted problem by exploring the 2D Hubbard model with cellular dynamical mean-field theory (CDMFT) solved by continuous-time quantum Monte Carlo (CTQMC) in the hybridization expansion. We characterize the dependence of the above quantities on interaction U, next nearest-neighbor hopping t’ and Zeeman-coupled magnetic field h. The short-range correlation-driven pseudogap is resilient to typical values of h. We recover the aforementioned experimental observations.

[1] S. Badoux et al., Nature 531, 210-214
[2] C. Collignon et al., Phys. Rev. B 95, 224517
[3] B. Loret et al., arXiv:1703.00794
[4] J. Tallon (unpublished)
[5] H. Bragança et al., arXiv:1708.02084
[6] W. Wu et al., arXiv:1707.06602