Study on single photon emission utilizing isoelectronic traps

点击翻译按钮获取中文摘要

Single photon emitting devices are expected to play an important role in the quantum information technology, such as quantum cryptography and quantum computing. In this study, we have studied the properties of photoluminescence due to single isoelectronic traps in nitrogen delta-doped GaAs and GaP to examine the prospect for applications to single photon emitting devices. We have optimized growth conditions to obtain nitrogen pairs with specific configurations. As a result, we have successfully observed sharp photoluminescence lines due to a limited number of isoelectronic traps within a diameter of 1 μm for nitrogen delta-doped GaAs with low nitrogen concentrations. This result shows good prospects for the single photon emitting device utilizing single isoelectronic traps. We have also observed twin photoluminescence peaks from single isoelectronic traps due to nitrogen pairs in nitrogen delta-doped GaAs. The twin photoluminescence peaks showed almost the same intensity and linear polarizations which are completely orthogonal to each other. This unique phenomenon has prospects of applications to novel optoelectronic devices. Furthermore, we have investigated the excitation power density and nitrogen concentration dependence of the changes in the radiative efficiency of GaAsN alloys to examine the mechanism of the novel phenomenon that photoexcitation at low temperatures improves the radiative efficiency. We have found that the radiative efficiency improvement is closely related to local structural changes by using in-situ micro Raman scattering spectroscopy.