Publications

Results 226–250 of 457

Search results

Jump to search filters

Gallium nitride nanotube lasers

Applied Physics Letters

Li, Changyi; Liu, Sheng; Hurtado, Antonio; Wright, Jeremy B.; Xu, Huiwen; Luk, Ting S.; Figiel, Jeffrey J.; Brener, Igal; Brueck, Steven R.J.; Wang, George T.

Lasing is demonstrated from gallium nitride nanotubes fabricated using a two-step top-down technique. By optically pumping, we observed characteristics of lasing: a clear threshold, a narrow spectral, and guided emission from the nanotubes. In addition, annular lasing emission from the GaN nanotube is also observed, indicating that cross-sectional shape control can be employed to manipulate the properties of nanolasers. The nanotube lasers could be of interest for optical nanofluidic applications or application benefitting from a hollow beam shape.

More Details
TYPE Journal Article YEAR 2014
DOIOSTI

Optical Strong Coupling between near-Infrared Metamaterials and Intersubband Transitions in III-Nitride Heterostructures

ACS Photonics

Campione, Salvatore; Moseley, Michael W.; Wierer, Jonathan J.; Allerman, Andrew A.; Wendt, Joel R.; Brener, Igal

(Figure Presented) We present the design, realization, and characterization of optical strong light-matter coupling between intersubband transitions within a semiconductor heterostructures and planar metamaterials in the near-infrared spectral range. The strong light-matter coupling entity consists of a III-nitride intersubband superlattice heterostructure, providing a two-level system with a transition energy of ∼0.8 eV (λ ∼1.55 μm) and a planar "dogbone" metamaterial structure. As the bare metamaterial resonance frequency is varied across the intersubband resonance, a clear anticrossing behavior is observed in the frequency domain. This strongly coupled entity could enable the realization of electrically tunable optical filters, a new class of efficient nonlinear optical materials, or intersubband-based light-emitting diodes.

More Details
TYPE Journal Article YEAR 2014
DOIOSTIScopus

Doping-tunable thermal emission from plasmon polaritons in semiconductor epsilon-near-zero thin films

Applied Physics Letters

Brener, Igal; Klem, John F.; Luk, Ting S.; Jun, Young C.; Ellis, R.

We utilize the unique dispersion properties of leaky plasmon polaritons in epsilon-near-zero (ENZ) thin films to demonstrate thermal radiation control. Owing to its highly flat dispersion above the light line, a thermally excited leaky wave at the ENZ frequency out-couples into free space without any scattering structures, resulting in a narrowband, wide-angle, p-polarized thermal emission spectrum. We demonstrate this idea by measuring angle- and polarization-resolved thermal emission spectra from a single layer of unpatterned, doped semiconductors with deep-subwavelength film thickness (d / λ 0 ∼ 6 × 10 - 3, where d is the film thickness and λ 0 is the free space wavelength). We show that this semiconductor ENZ film effectively works as a leaky wave thermal radiation antenna, which generates far-field radiation from a thermally excited mode. The use of semiconductors makes the radiation frequency highly tunable by controlling doping densities and also facilitates device integration with other components. Therefore, this leaky plasmon polariton emission from semiconductor ENZ films provides an avenue for on-chip control of thermal radiation.

More Details
TYPE Journal Article YEAR 2014
DOIOSTIScopus
Results 226–250 of 457
Results 226–250 of 457
Top