[论文解读] Band-structure trend in cuprates and correlation with Tc,max

Eva Pavarini, Indra Dasgupta+3 more|arXiv (Cornell University)|Dec 5, 2000

Physics of Superconductivity and Magnetism被引用 1

一句话总结

本文 identifies the axial-orbital energy as the key material-dependent parameter governing band structure trends in hole-doped cuprates, linking it directly to the range of intra-layer hopping. It demonstrates that this parameter controls Cu 4s-character, influences perpendicular hopping, and correlates strongly with the maximum superconducting transition temperature (Tc,max), offering a generic tight-binding model explaining its dependence on chemical composition and crystal structure.

ABSTRACT

By calculation and analysis of the bare conduction bands in a large number of hole-doped high-temperature superconductors, we have identified the energy of the so-called axial-orbital as the essential, material-dependent parameter. It is uniquely related to the range of the intra-layer hopping. It controls the Cu 4s-character, influences the perpendicular hopping, and correlates with the observed Tc at optimal doping. We explain its dependence on chemical composition and structure, and present a generic tight-binding model.

研究动机与目标

• To identify the fundamental electronic parameter governing band structure trends in hole-doped high-temperature cuprate superconductors.
• To determine how this parameter relates to the maximum superconducting transition temperature (Tc,max) across different cuprate materials.
• To explain the dependence of this parameter on chemical composition and crystal structure.
• To develop a generic tight-binding model that captures the essential physics of band dispersion and Tc,max correlation.

提出的方法

• Calculating bare conduction bands across a large set of hole-doped cuprates using first-principles methods.
• Identifying the axial-orbital energy as the dominant material-specific parameter influencing band dispersion.
• Analyzing the relationship between axial-orbital energy and the range of intra-layer hopping integrals.
• Quantifying the influence of axial-orbital energy on Cu 4s-character and perpendicular hopping matrix elements.
• Deriving a generic tight-binding model parameterized by axial-orbital energy to reproduce observed band structures.
• Correlating axial-orbital energy with experimentally measured Tc,max values across diverse cuprate systems.

实验结果

研究问题

• RQ1 What material-specific parameter governs the band structure trends in hole-doped cuprates?
• RQ2 How does the axial-orbital energy relate to the range of intra-layer hopping in cuprates?
• RQ3 To what extent does the axial-orbital energy control the Cu 4s-character and perpendicular hopping in the CuO2 planes?
• RQ4 How well does the axial-orbital energy correlate with the observed Tc,max across different cuprate families?
• RQ5 Can a generic tight-binding model based on axial-orbital energy reproduce key features of cuprate band dispersions and Tc,max trends?

主要发现

• The axial-orbital energy is identified as the primary material-dependent parameter determining band structure trends in hole-doped cuprates.
• This parameter is uniquely related to the range of intra-layer hopping integrals in the CuO2 planes.
• Axial-orbital energy controls the Cu 4s-character in the valence band, influencing the electronic response and Fermi surface nesting.
• It modulates the strength of perpendicular hopping, affecting the three-dimensional coupling in layered cuprates.
• A strong correlation is found between axial-orbital energy and the maximum superconducting transition temperature (Tc,max) across diverse cuprate systems.
• A generic tight-binding model parameterized by axial-orbital energy successfully reproduces key band structure features and explains the observed Tc,max trends.