title: Bias-enhanced optical pH response of group III-nitride nanowires.
abstract: We show that the photoluminescence intensity of GaN and InGaN nanowires in electrolytes sensitively responds to variations of the pH value and the applied bias. The realization of an electrochemical working point allows pH detection with a resolution better than 0.05 pH. The observed effects are attributed to bias-dependent nonradiative recombination processes competing with interband transitions. The results show that group III-nitride nanowires are excellently suited as nanophotonic pH sensor elements.
authors.affiliation: I. Physikalisches Institut, Justus-Liebig-Universität Gießen, Heinrich-Buff-Ring 16, D-35392 Gießen, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Wallys
authors.forename: Jörg
authors.initials: J
authors.lastname: Teubert
authors.forename: Florian
authors.initials: F
authors.lastname: Furtmayr
authors.forename: Detlev M
authors.initials: DM
authors.lastname: Hofmann
authors.forename: Martin
authors.initials: M
authors.lastname: Eickhoff
mesh_terms: D055664:Electrochemical Techniques; D004573:Electrolytes / Q000737:chemistry; D005708:Gallium / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007204:Indium / Q000737:chemistry*; D049449:Luminescence; D053770:Nanowires / Q000737:chemistry*
chemical_list: D004573:Electrolytes; D007204:Indium; C473348:gallium nitride; D005708:Gallium