Zn doped GaN for single‐photon emission

Abstract

In this work we report on the optical investigation of Zn doped GaN films fabricated by metal organic chemical vapor deposition. The samples show bright emission in the blue spectral range around 2.9 eV when Si codoping is provided. This emission is suggested to be used for single‐photon emission, thus the density of the Zn‐Si pairs was drastically reduced leading to a decrease of the blue luminescence. For electrically excited single‐photon sources these Zn‐Si pairs have to be incorporated into LEDs, therefore we fabricated GaN‐based nano‐LEDs which show electroluminescence at 430 nm (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Observation of sharp emission lines from Zn-doped GaN

“…Microphotoluminescence measurements performed under excitation above the GaN bandgap reveal the typical broadband blue luminescence expected from Zn-related defects in the range of 400 nm-500 nm, which is likely to involve a mixture of Zn dopants substituting both Ga and N lattice sites, 12,15) and possibly recombination via an intermediate shallow donor state. 11,13) Interestingly, however, we are able to observe several spatially localized sharp emission lines on the low energy side of the emission spectra from the Zndoped samples. A selection of these sharp lines from different areas of the sample and under differrent excitation conditions (using 355 and 325 nm excitation) can be seen in Fig.…”

“…Although this broadened emission was of interest in early blue LED development, Zn doping is still of interest for the fundamental study of the optical properties of defects in crystals, and for the possible future development of novel single photon emitters. 13,14) Indeed, single photon emission in the blue range of the spectrum would be advantageous due to the availability of efficient photon detectors. However, to date, only the aforementioned broad emission bands from highly doped samples have been studied.…”