High temperature superconductivity in dimer array systems

TL;DR

This paper investigates high-temperature superconductivity in dimer array systems within the Hubbard model, showing that certain lattice arrangements can significantly increase the transition temperature compared to traditional models.

Contribution

It demonstrates that dimer array systems can achieve much higher superconducting transition temperatures, expanding potential materials and lattice configurations for high-$T_c$ superconductivity.

Findings

Transition temperature $T_c$ is much higher in dimer array systems.

Superconductivity can be realized in both $d$-electron and $p$-electron systems.

Dimer arrangements enhance superconducting properties compared to simple square lattices.

Abstract

Superconductivity in the Hubbard model is studied on a series of lattices in which dimers are coupled in various types of arrays. Using fluctuation exchange method and solving the linearized Eliashberg equation, the transition temperature $T_c$ of these systems is estimated to be much higher than that of the Hubbard model on a simple square lattice, which is a model for the high $T_c$ cuprates. We conclude that these `dimer array' systems can generally exhibit superconductivity with very high $T_c$. Not only $d$-electron systems, but also $p$-electron systems may provide various stages for realizing the present mechanism.