title: Surface Chemically Switchable Ultraviolet Luminescence from Interfacial Two-Dimensional Electron Gas.
abstract: We report intense, narrow line-width, surface chemisorption-activated and reversible ultraviolet (UV) photoluminescence from radiative recombination of the two-dimensional electron gas (2DEG) with photoexcited holes at LaAlO3/SrTiO3. The switchable luminescence arises from an electron transfer-driven modification of the electronic structure via H-chemisorption onto the AlO2-terminated surface of LaAlO3, at least 2 nm away from the interface. The control of the onset of emission and its intensity are functionalities that go beyond the luminescence of compound semiconductor quantum wells. Connections between reversible chemisorption, fast electron transfer, and quantum-well luminescence suggest a new model for surface chemically reconfigurable solid-state UV optoelectronics and molecular sensing.
authors.forename: Mohammad A
authors.initials: MA
authors.lastname: Islam
authors.affiliation: The Makineni Theoretical Laboratories, Department of Chemistry, University of Pennsylvania , Philadelphia, Pennsylvania 19104, United States.
authors.forename: Diomedes
authors.initials: D
authors.lastname: Saldana-Greco
authors.forename: Zongquan
authors.initials: Z
authors.lastname: Gu
authors.affiliation: The Makineni Theoretical Laboratories, Department of Chemistry, University of Pennsylvania , Philadelphia, Pennsylvania 19104, United States.
authors.forename: Fenggong
authors.initials: F
authors.lastname: Wang
authors.affiliation: Department of Materials Science & Engineering, University of Illinois at Urbana-Champaign , Urbana, Illinois 61801, United States.
authors.forename: Eric
authors.initials: E
authors.lastname: Breckenfeld
authors.affiliation: Department of Physics, Temple University , Philadelphia, Pennsylvania 19122, United States.
authors.forename: Qingyu
authors.initials: Q
authors.lastname: Lei
authors.affiliation: Department of Materials Science and Engineering, University of California, Berkeley , Berkeley, California 94720, United States.
authors.forename: Ruijuan
authors.initials: R
authors.lastname: Xu
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Hawley
authors.affiliation: Department of Physics, Temple University , Philadelphia, Pennsylvania 19122, United States.
authors.forename: X X
authors.initials: XX
authors.lastname: Xi
authors.affiliation: Department of Materials Science and Engineering, University of California, Berkeley , Berkeley, California 94720, United States.
authors.forename: Lane W
authors.initials: LW
authors.lastname: Martin
authors.affiliation: The Makineni Theoretical Laboratories, Department of Chemistry, University of Pennsylvania , Philadelphia, Pennsylvania 19104, United States.
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Rappe
authors.forename: Jonathan E
authors.initials: JE
authors.lastname: Spanier
mesh_terms: D000537:Aluminum Oxide / Q000737:chemistry*; D015374:Biosensing Techniques; D004583:Electrons; D005740:Gases / Q000737:chemistry*; D049449:Luminescence; D010087:Oxides / Q000737:chemistry; D013324:Strontium / Q000737:chemistry; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry; D014466:Ultraviolet Rays
chemical_list: D005740:Gases; D010087:Oxides; D014025:Titanium; D000537:Aluminum Oxide; C119252:strontium titanium oxide; D013324:Strontium
keywords: LaAlO3/SrTiO3; Two-dimensional electron gas; chemisorption; photoluminescence