Persistent photoconductivity in oxygen deficient YBCO/LCMO superlattices grown by PLD

TL;DR

This study demonstrates significant persistent photoconductivity in oxygen-deficient YBCO/LCMO superlattices grown by PLD, highlighting the influence of oxygen deficiency and interface properties on photoconductivity.

Contribution

It reveals that persistent photoconductivity in superlattices is similar to single-layer films and differs from sputtered bilayers, emphasizing the role of interface charge transfer and preparation details.

Findings

PPC scales with oxygen deficiency in superlattices

Contradicts previous transient photoconductivity observations

Highlights interface permeability's role in photoconductivity

Abstract

We report a large persistent photoconductivity (PPC) in oxygen reduced PLD grown YBa2Cu3O7-{\delta}/La2/3Ca1/3MnO3-y (YBCO/LCMO) superlattices scaling with the oxygen deficiency and being similar to that observed in single layer YBa2Cu3O7-{\delta} films. These results contradict previous observations where in sputtered bilayer samples only a transient photoconductivity (TPC) was found. We argue that the PPC effect in superlattices is caused by the PPC effect due to the YBa2Cu3O7-x layers with limited charge transfer to La2/3Ca1/3MnO3-y. The discrepancy arises from the different permeability of charges across the interface and shed light on the sensitivity of oxide interface properties on details of their preparation.