Generalized One-Band Model Based on Zhang-Rice Singlets for Tetragonal CuO

Tetragonal CuO (T-CuO) has attracted attention because of its structure similar to that of the cuprates. It has been recently proposed as a compound whose study can give an end to the long debate about the proper microscopic modeling for cuprates. In this work, we rigorously derive an effective one-band generalized $t-J$ model for T-CuO, based on orthogonalized Zhang-Rice singlets, and make an estimative calculation of its parameters, based on previous ab initio calculations. By means of the self-consistent Born approximation, we then evaluate the spectral function and the quasiparticle dispersion for a single hole doped in antiferromagnetically ordered half filled T-CuO. Our predictions show very good agreement with angle-resolved photoemission spectra and with theoretical multiband results. We conclude that a generalized $t-J$ model remains the minimal Hamiltonian for a correct description of single-hole dynamics in cuprates.

Figure 1

The two possible magnetic ground states for T-CuO: $\mathbf{Q}=(0,\pi )$ (left) and $\mathbf{Q}=(\pi ,0)$ (right). The coordinate versors point in the directions of $\mathbf{c}$ and $\mathbf{d}$. Arrows indicate spins at Cu sites, and circles correspond to the O sites.

Figure 2

Quasiparticle dispersion relation (relative to $\mathrm{\Gamma }$) along the path marked in the inset, the same as the one measured in the ARPES experiment in Ref. [20]. A broadening equivalent to 20 meV was applied to the spectral functions (see the text).

Figure 3

SCBA intensity map along the same path as in Fig. 2. The assumed magnetic order is $(\pi ,0)$.

Figure 4

SCBA hole dispersion relation in units of $J$ (0.15 eV) along the path marked in the inset. Black dashed line: The result corresponding to $t_0=0$ (decoupled sublattices). Blue full line: The full result with $t_0=-184\mathrm{meV}$.