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

Area of Science:

• Condensed Matter Physics
• Materials Science
• Quantum Chemistry

Background:

• Tetragonal copper oxide (T-CuO) exhibits structural similarities to cuprates, making it a key material for understanding high-temperature superconductivity.
• The precise microscopic modeling of cuprates remains a significant challenge in condensed matter physics.

Purpose of the Study:

• To rigorously derive an effective one-band generalized t-J model for T-CuO.
• To investigate single-hole dynamics in T-CuO using theoretical calculations.
• To assess the validity of the generalized t-J model for cuprate systems.

Main Methods:

• Derivation of an effective one-band generalized t-J model using orthogonalized Zhang-Rice singlets.
• Estimation of model parameters based on prior ab initio calculations.
• Evaluation of spectral function and quasiparticle dispersion via the self-consistent Born approximation.

Main Results:

• The derived generalized t-J model provides a minimal yet accurate description of T-CuO.
• Calculated spectral function and quasiparticle dispersion align well with experimental angle-resolved photoemission spectra.
• Theoretical predictions show strong agreement with existing multiband theoretical results.

Conclusions:

• The generalized t-J model is a suitable minimal Hamiltonian for describing single-hole dynamics in cuprates.
• T-CuO serves as a valuable system for studying and resolving debates in cuprate microscopic modeling.
• The study validates the approach of using effective models derived from fundamental principles for complex materials.