title: Photo-resistive properties of LaAl0.6Cr0.4O3/SrTiO3 heterostructures: a comparative study with LaAlO3/SrTiO3.
abstract: We report photoconductivity measurements on LaAl(1-x)Cr(x)O3/SrTiO3 (x=0, 0.4) heterostructures. A polar layer modification of metallic LaAlO3/SrTiO3 heterostructure with Cr in the Al sites resulted in an increased photo-response (PR) and relaxation time, in addition to a distinct shift in the spectral weight toward the red end of the spectrum. The visible light photoconductivity is explained by d-d photoconductivity of Cr3+ valence states of the x=0.4 sample. Besides the established UV sensitivity, we observe a weak peak in PR around 690 nm possibly emanating from the mid-gap states arising from oxygen vacancies.
authors.forename: Aswin
authors.initials: A
authors.lastname: V
authors.forename: Pramod
authors.initials: P
authors.lastname: Kumar
authors.forename: Prabir
authors.initials: P
authors.lastname: Pal
authors.forename: Anjana
authors.initials: A
authors.lastname: Dogra