We describe the growth of InGaN quantum dots (QDs) by metalorganic vapor phase epitaxy. A thin InGaN epilayer is grown on a GaN buffer layer and then annealed at the growth temperature in molecular nitrogen inducing quantum dot formation. Microphotoluminescence studies of these QDs reveal sharp peaks with typical linewidths of $\text{∼700\hspace{0.17em}μ}\mathrm{eV}$ at 4.2 K, the linewidth being limited by the spectral resolution. Time-resolved photoluminescence suggests that the excitons in these structures have lifetimes in excess of 2 ns at 4.2 K.

UV irradiation of aligned diphenylalanine peptide nanotubes (FF-PNTs) decorated with plasmonic silver nanoparticles (Ag NPs) enables photo-induced surface-enhanced Raman spectroscopy. UV-induced charge transfer facilitates a chemical enhancement that provides up to a 10-fold increase in surface-enhanced Raman intensity and allows the detection of a wide range of small molecules and low Raman cross-section molecules at concentrations as low as 10^–13 M. The aligned FF-PNT/Ag NP template further prevents photodegradation of the molecules under investigation. Our results demonstrate that FF-PNTs can be used as an alternative material to semiconductors such as titanium dioxide for photo-induced surface-enhanced Raman spectroscopy applications.

We report measurements of optical transitions in single III/V (InGaN) quantum dots as a function of time. Temporal fluctuations in microphotoluminescence peak position and linewidth are demonstrated and attributed to spectral diffusion processes. The origin of this temporal variation is ascribed to randomly generated local electric fields inducing a Stark shift in the optical emission peaks of the InGaN quantum dots.

Most experts agree that it is too early to say how quantum computers will eventually be built, and several nanoscale solidstate schemes are being implemented in a range of materials. Nanofabricated...