title: Electroluminescence from nanocrystals in an electromigrated gap composed of two different metals.
abstract: We present a technique for making nanoscale gaps with work function offsets based on electromigrating leads composed of two different metals. Electroluminescence spectra from plain metal gaps with and without CdSe/ZnS (core/shell) nanocrystals are qualitatively very similar and exhibit features that are much broader than the photoluminescence spectra obtained from the same nanocrystals. These observations can be explained by inelastic scattering of conduction electrons in the metal leads or by electroluminescence from small metallic clusters that can form during the fabrication process. However, electroluminescence that spectrally coincides with nanocrystal photoluminescence can be observed in devices containing nanocrystals formed by electromigrating Pt leads bridged with small indium islands. This suggests that electromigrating leads made of different metals is a promising route to fabricating nanoscale gaps with work function offsets for optoelectronic devices.
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: August
authors.initials: A
authors.lastname: Dorn
authors.forename: Hao
authors.initials: H
authors.lastname: Huang
authors.forename: Moungi G
authors.initials: MG
authors.lastname: Bawendi
mesh_terms: D019187:Cadmium Compounds / Q000737:chemistry* / Q000528:radiation effects; D003460:Crystallization / Q000379:methods*; D004574:Electromagnetic Fields; D008163:Luminescent Measurements / Q000379:methods*; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology / Q000379:methods; D010316:Particle Size; D018036:Selenium Compounds / Q000737:chemistry* / Q000528:radiation effects; D017967:Zinc Compounds / Q000737:chemistry* / Q000528:radiation effects
chemical_list: D019187:Cadmium Compounds; D046911:Macromolecular Substances; D018036:Selenium Compounds; D017967:Zinc Compounds; C058667:cadmium selenide; C044696:zinc selenide