Linearly polarized photoluminescence of InGaN quantum disks embedded in GaN nanorods

Abstract

We have investigated the emission from InGaN/GaN quantum disks grown on the tip of GaN nanorods. The emission at 3.21 eV from the InGaN quantum disk doesn’t show a Stark shift, and it is linearly polarized when excited perpendicular to the growth direction. The degree of linear polarization is about 39.3% due to the anisotropy of the nanostructures. In order to characterize a single nanostructure, the quantum disks were dispersed on a SiO2 substrate patterned with a metal reference grid. By rotating the excitation polarization angle from parallel to perpendicular relative to the nanorods, the variation of overall PL for the 3.21 eV peak was recorded and it clearly showed the degree of linear polarization (DLP) of 51.5%.

2D III‐Nitride Materials: Properties, Growth, and Applications

“…[ 54–61 ] 0D quantum dots and 1D nanowires (nanorods) of III‐nitride materials have been fabricated by various growth methods, and their properties have been widely studied. [ 62–66 ] However, as the molecular structures of 0D and 1D III‐nitride materials are very similar to their bulk structures, only small modulation effects of the properties are found. On contrary, 2D materials exhibit structures distinct from the bulk materials, leading to different properties.…”

Underpotential‐Assisted Electrodeposition of Highly Crystalline and Smooth Thin Film of Bismuth

“…Finally, CPL microscopy underlined an unexpected weak optical anisotropy all over the sample, which becomes strong in a couple of regions, whose size is of approximately a hundred microns and whose shape recalls a grain boundary. The optical anisotropy was evaluated by using a rotating circular stage and acquiring photos of the sample every 10°, then, the mean grey value in the identified areas was measured.…”

Origin of the spectral red-shift and polarization patterns of self-assembled InGaN nanostructures on GaN nanowires

“…17 For NWs of larger diameter, the second, purely classical effect dominates, until the NW diameter becomes large enough to be comparable to bulk material. 2 Depolarization ratios of GaN NWs with embedded InGaN QWs 5,18–23 and quantum dots (QDs) have been frequently reported, 12,24–26 but not for InGaN NWs. Especially in structures containing QDs in a wire, i.e.…”

“…17 For NWs of larger diameter, the second, purely classical effect dominates, until the NW diameter becomes large enough to be comparable to bulk material. 2 Depolarization ratios of GaN NWs with embedded InGaN QWs 5,[18][19][20][21][22][23] and quantum dots (QDs) have been frequently reported, 12,[24][25][26] but not for InGaN NWs. Especially in structures containing QDs in a wire, i.e., embedded regions that act as QDs, the emission properties can differ strongly due to non-or semi-polar side-facets and the emission typically shows polarization perpendicular to the NW axis.…”