On the superconducting critical temperature in multiband disordered\\ $LaAlO_{3}/SrTiO_{3}$ interfaces.

Venditti G., Grilli M., Caprara S.
  Martedì 13/09   09:00 - 13:30   Aula D - Marianna Ciccone   II - Fisica della materia   Presentazione
$LaAlO_{3}/SrTiO_{3}$ interfaces are a nice example of a two-dimensional disordered system that can host multi-band superconductivity once the carrier density of the electron gas is suitably tuned by means of gate voltage. Here, the interplay of two-dimensionality, multi-band character and disorder can largely affect the superconducting critical temperature $T_{c}$, suppressing superconductivity and circumventing Anderson's theorem. We propose a realistic two-band disordered model based on experimentally determined parameters to study such interplay. While confirming that a repulsive inter-band coupling favors the $T_{c}$ suppression, we show that disorder alone can mix the two bands, generating a more pronounced suppression of the critical temperature in the vicinity of the Lifshitz transition. Finally, this study allowed us to disentangle microscopic from mesoscopic disorder effects, since the global behavior of $T_{c}$ is well captured only if the strongly inhomogeneous nature of such compounds is considered.