Electrically pumped lasing from single ZnO micro/nanowire and poly(3,4-ethylenedioxythiophene):poly(styrenexulfonate) hybrid heterostructures

We report electrically driven ultraviolet lasing by electrical injection in a single ZnO micro/nanowire. Heterojunctions were fabricated by contacting poly(3,4-ethylenedioxythiophene): poly(styrenexulfonate) (PEDOT:PSS) with one end of a single ZnO wire. At an excitation injection of similar to 1 A/cm(2), the electroluminescence spectrum showed a near-ultraviolet lasing action. This phenomenon was understood based on whispering-gallery mode, which results from trajectories that traverse a polygonal cross-section near the edges of the cylinder. The reduction of some modes was associated with the surface states or defects and the resonance below the intrinsic exciton emission of ZnO is related to electron accumulation at the polymer/ZnO interface. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4739430]