LCAO model for 3D Fermi surface of high-Tc cuprate Tl2Ba2CuO6+δ

• Published in: The European physical journal. B, Condensed matter physics Condensed matter physics, 2010, Vol.73 (1), p.109-115
• Main Authors: Stoev, M., Mishonov, T. M.
• Format: Article
• Language: English
• Subjects: Complex Systems; Condensed Matter Physics; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Electronic structure; Exact sciences and technology; Fluid- and Aerodynamics; Physics; Physics and Astronomy; Properties of type I and type II superconductors; Solid State and Materials; Solid State Physics; Superconductivity
• ISSN: 1434-6028; 1434-6036
• DOI: 10.1140/epjb/e2009-00407-9

A simple analytical formula for three-dimensional Fermi surface (3D FS) of is derived in the framework of LCAO approximation spanned over Cu 4 s , Cu 3d , O 2p x and O 2p y states. This analytical result can be used for fitting of experimental data for 3D FS such as polar angle magnetoresistance oscillation. The model takes into account effective copper-copper hopping amplitude t ss between Cu 4s orbitals from neighbouring layers. The acceptable correspondence with the experimental data gives a hint that the t ss amplitude dominates in formation of coherent 3D FS, and other oxygen-oxygen and copper-oxygen amplitudes are rather negligible. For absolute determination of the hopping parameters a simple electronic experiment with a field effect transistor type microstructure is suggested. The thin superconductor layer is the source-drain channel of the layered structure where an AC current is applied.