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Photoresponse dynamics in amorphous-LaAlO(3)/SrTiO(3) interfaces
The time-resolved photoconductance of amorphous and crystalline LaAlO(3)/SrTiO(3) interfaces, both hosting an interfacial 2-dimensional electron gas, is investigated under irradiation by variable-wavelengths, visible or ultraviolet photons. Unlike bare SrTiO(3) single crystals, showing relatively sm...
Autores principales: | , , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Nature Publishing Group
2015
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4323649/ https://www.ncbi.nlm.nih.gov/pubmed/25670163 http://dx.doi.org/10.1038/srep08393 |
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author | Di Gennaro, Emiliano Coscia, Ubaldo Ambrosone, Giuseppina Khare, Amit Granozio, Fabio Miletto di Uccio, Umberto Scotti |
author_facet | Di Gennaro, Emiliano Coscia, Ubaldo Ambrosone, Giuseppina Khare, Amit Granozio, Fabio Miletto di Uccio, Umberto Scotti |
author_sort | Di Gennaro, Emiliano |
collection | PubMed |
description | The time-resolved photoconductance of amorphous and crystalline LaAlO(3)/SrTiO(3) interfaces, both hosting an interfacial 2-dimensional electron gas, is investigated under irradiation by variable-wavelengths, visible or ultraviolet photons. Unlike bare SrTiO(3) single crystals, showing relatively small photoconductance effects, both kinds of interfaces exhibit an intense and highly persistent photoconductance with extraordinarily long characteristic times. The temporal behaviour of the extra photoinduced conductance persisting after light irradiation shows a complex dependence on interface type (whether amorphous or crystalline), sample history and irradiation wavelength. The experimental results indicate that different mechanisms of photoexcitation are responsible for the photoconductance of crystalline and amorphous LaAlO(3)/SrTiO(3) interfaces under visible light. We propose that the response of crystalline samples is mainly due to the promotion of electrons from the valence bands of both SrTiO(3) and LaAlO(3). This second channel is less relevant in amorphous LaAlO(3)/SrTiO(3), where the higher density of point defects plays instead a major role. |
format | Online Article Text |
id | pubmed-4323649 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2015 |
publisher | Nature Publishing Group |
record_format | MEDLINE/PubMed |
spelling | pubmed-43236492015-02-20 Photoresponse dynamics in amorphous-LaAlO(3)/SrTiO(3) interfaces Di Gennaro, Emiliano Coscia, Ubaldo Ambrosone, Giuseppina Khare, Amit Granozio, Fabio Miletto di Uccio, Umberto Scotti Sci Rep Article The time-resolved photoconductance of amorphous and crystalline LaAlO(3)/SrTiO(3) interfaces, both hosting an interfacial 2-dimensional electron gas, is investigated under irradiation by variable-wavelengths, visible or ultraviolet photons. Unlike bare SrTiO(3) single crystals, showing relatively small photoconductance effects, both kinds of interfaces exhibit an intense and highly persistent photoconductance with extraordinarily long characteristic times. The temporal behaviour of the extra photoinduced conductance persisting after light irradiation shows a complex dependence on interface type (whether amorphous or crystalline), sample history and irradiation wavelength. The experimental results indicate that different mechanisms of photoexcitation are responsible for the photoconductance of crystalline and amorphous LaAlO(3)/SrTiO(3) interfaces under visible light. We propose that the response of crystalline samples is mainly due to the promotion of electrons from the valence bands of both SrTiO(3) and LaAlO(3). This second channel is less relevant in amorphous LaAlO(3)/SrTiO(3), where the higher density of point defects plays instead a major role. Nature Publishing Group 2015-02-11 /pmc/articles/PMC4323649/ /pubmed/25670163 http://dx.doi.org/10.1038/srep08393 Text en Copyright © 2015, Macmillan Publishers Limited. All rights reserved http://creativecommons.org/licenses/by/4.0/ This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder in order to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/ |
spellingShingle | Article Di Gennaro, Emiliano Coscia, Ubaldo Ambrosone, Giuseppina Khare, Amit Granozio, Fabio Miletto di Uccio, Umberto Scotti Photoresponse dynamics in amorphous-LaAlO(3)/SrTiO(3) interfaces |
title | Photoresponse dynamics in amorphous-LaAlO(3)/SrTiO(3) interfaces |
title_full | Photoresponse dynamics in amorphous-LaAlO(3)/SrTiO(3) interfaces |
title_fullStr | Photoresponse dynamics in amorphous-LaAlO(3)/SrTiO(3) interfaces |
title_full_unstemmed | Photoresponse dynamics in amorphous-LaAlO(3)/SrTiO(3) interfaces |
title_short | Photoresponse dynamics in amorphous-LaAlO(3)/SrTiO(3) interfaces |
title_sort | photoresponse dynamics in amorphous-laalo(3)/srtio(3) interfaces |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4323649/ https://www.ncbi.nlm.nih.gov/pubmed/25670163 http://dx.doi.org/10.1038/srep08393 |
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