title: Semiconductor nanowire ring resonator laser.
abstract: Nanowires of the wide band-gap semiconductor gallium nitride (GaN) have been shown to act as room-temperature uv lasers. Recent advances in nanomanipulation have made it possible to modify the shape of these structures from a linear to a pseudoring conformation. Changes to the optical boundary conditions of the lasing cavity affect the structure's photoluminescence, photon confinement, and lasing as a function of ring diameter. For a given cavity, ring-mode redshifting is observed to increase with decreasing ring diameter. Significant shifts, up to 10 nm for peak emission values, are observed during optical pumping of a ring resonator nanolaser compared to its linear counterpart. The shifting appears to result from conformational changes of the cavity rather than effects such as band-gap renormalization, allowing the mode spacing and position to be tuned with the same nanowire gain medium.
authors.affiliation: Department of Chemistry, University of California at Berkeley, Berkeley, CA 94720, USA.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Pauzauskie
authors.forename: Donald J
authors.initials: DJ
authors.lastname: Sirbuly
authors.forename: Peidong
authors.initials: P
authors.lastname: Yang