Transverse-microcavity modulation of photoluminescence from GaN nanowires

Spatially resolved photoluminescence (PL) spectra from tapered GaN nanowires (NWs) with triangular cross section exhibit marked intensity modulations along the NW length. The modulation periodicity is attributed to previously unrecognized, leaky transverse standing-waves that occur when the PL wavelength matches path length criteria. These Fabry-Perot modes can affect optical measurements in transparent nanostructures even for dimensions less than similar to lambda/2n, where lambda is the free-space wavelength and n is the index of refraction. [doi: 10.1063/1.3488018]