Enhanced surface-and-interface coupling in Pd-nanoparticle-coated LaAlO3/SrTiO3heterostructures: Strong gas- and photo-induced conductance modulation

Haeri Kim, Ngai Yui Chan, Jiyan Dai, Dong Wook Kim

Research output: Journal article publicationJournal articleAcademic researchpeer-review

22 Citations (Scopus)

Abstract

Pd nanoparticle (NP) coated LaAlO3/SrTiO3(LAO/STO) heterointerface exhibits more notable conductance (G) change while varying the ambient gas (N2, H2/N2, and O2) and illuminating with UV light (wavelength: 365 nm) than a sample without the NPs. Simultaneous Kelvin probe force microscopy and transport measurements reveal close relationships between the surface work function (W) and G of the samples. Quantitative analyses suggest that a surface adsorption/desorption-mediated reaction and redox, resulting in a band-alignment modification and charge-transfer, could explain the gas- and photo-induced conductance modulation at the LAO/STO interface. Such surface-and-interface coupling enhanced by catalytic Pd NPs is a unique feature, quite distinct from conventional semiconductor hetero-junctions, which enables the significant conductance tunability at ultrathin oxide heterointerfaces by external stimuli.
Original languageEnglish
Article number8531
JournalScientific Reports
Volume5
DOIs
Publication statusPublished - 1 Jan 2014

ASJC Scopus subject areas

  • General

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