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  • Letter
  • Open Access

Inhomogeneous superconductivity in (001), (110), and (111) KTaO3 two-dimensional electronic gases: Effect of electronic confinement on the transition temperature

Mattia Trama1,2,*, Roberta Citro1,2,3, and Carmine Antonio Perroni3,4,5,†

  • *Contact author: mtrama@unisa.it
  • †Contact author: carmine.perroni@unina.it
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Phys. Rev. B 114, L140501 – Published 8 September, 2026

DOI: https://doi.org/10.1103/dmjz-y7c6

Abstract

Experimental observations on KTaO3 superconductivity report widely different critical temperatures with a clear hierarchy among different crystallographic orientations. Accounting for spatial confinement, we connect the inhomogeneous superconducting order parameter with the spatial extent of the two-dimensional electron gas. We reproduce the observed hierarchy within a unified framework, based on a self-consistent tight-binding slab model with local spin-singlet s-wave pairing. The methods developed here can be readily extended to include more general interaction models, while still consistently including the characteristic spatial structure of the electron gas.

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Phys. Rev. B 114, L140501– Published 8 September, 2026
  • Received 20 April 2026
  • Revised 5 July 2026
  • Accepted 20 August 2026
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