Emergent superconducting stripes in two-orbital superconductors

TL;DR

This paper proposes a theoretical mechanism for the emergence of superconducting stripes in two-orbital superconductors, driven by intrinsic electronic interactions without disorder or competing phases.

Contribution

It introduces a two-orbital model demonstrating how superconducting stripes can form spontaneously in homogeneous systems, supported by auxiliary-field Monte Carlo simulations.

Findings

Superconducting stripes emerge naturally in the model.

Stripes are separated by non-superconducting regions.

The mechanism does not rely on disorder or charge inhomogeneity.

Abstract

Motivated by recent experiments in KTaO$_3$/EuO interface, we propose an intrinsic mechanism where superconducting stripes emerge naturally without involving disorder, charge inhomogeneity, or competing orders. Our theory is based on a two-orbital model of superconductivity, where one orbital displays a quasi-one-dimensional dispersion and the other orbital is more localized and contributes pairing interactions along the perpendicular direction. Our auxiliary-field Monte Carlo simulations demonstrate that the pairing amplitude exhibits spatial modulation such that the superconductivity naturally disaggregates into two-leg or three-leg superconducting stripes separated by non-superconducting blocks. Our work provides a promising scenario of emergent superconducting stripes in homogeneous two-dimensional systems and reveals unexpectedly rich physics in two-orbital superconductors for future materials design.