AIP conference proceedings

Role of on-site hole-phonon interaction of high-Tc superconductivity within Holstein t-J model

Krishanu Roy, Chumki Tarafdar, Nanda Kumar Ghosh

Published Jan 1, 2020• 1 citation

Abstract

Effect of on-site hole-phonon (h-ph) interaction within Holstein t-J model has been examined numerically using exact diagonalization (ED) technique within an 8 – site tilted square cluster at a hole doping <h>=0.25. We have applied periodic boundary conditions to obtain the basis states. It appears that with the increase of on-site h-ph interaction λ1 as well as phonon energy ω0, the ground state energy of the system reduces. Also, the enhancement of the number of phonons results in a significant decrease in ground state energy. At higher temperature, entropy decreases with λ1 as a result of the formation of S0 bipolarons. Low temperature specific heat indicates non-Fermi liquid behavior of the system.

DOI: 10.1063/5.0002270

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