AVS 60th International Symposium and Exhibition
    Nanometer-scale Science and Technology Tuesday Sessions
       Session NS-TuP

Paper NS-TuP13
Optical Properties of InN/InGaN/GaN Dot-in-a-Nanowire Heterostructure

Tuesday, October 29, 2013, 6:00 pm, Room Hall B

Session: Nanometer-scale Science and Technology Poster Session
Presenter: M.D. Kim, Chungnam National University, Republic of Korea
Correspondent: Click to Email
During the last few years, light sources have been investigated with application potential for the implementation of quantum information technologies. In this research field, quantum dots (QDs) have attracted considerable interest both as single photon light sources and high efficiency light sources . Single photon emission from semiconductor QDs has been reported for many different material systems covering different wavelengths and maximum operation temperatures. Group-III-nitrides have the prospect that the emission energy can be engineered over a wider spectral range by varying their alloy contents. In this study, we report a near infrared (IR) emission of InN/InGaN(In~11%)/GaN dot-in-a nanorods (NRs) grown by plasma-assisted molecular beam epitaxy (PAMBE) on Si(111) substrate. Catalyst-free InN/InGaN/GaN dot-in-a NRs were grown in holes of a patterned Si(111) substrate. Arrays of nano-holes with diameter of 80 nm on the Si substrate were obtained by reactive ion etching of polystyrene beads as a nano-hole mask. Scanning electron microscopy, X-ray diffraction, micro-photoluminescence (PL), and high-resolution transmission electron microscopy (HRTEM) were performed to investigate the NRs shape, micro-structural and optical characterizations. Fig. 1(a) show the TEM images of the InN/InGaN/GaN dot-in-a-NRs heterostructure. It is seen that the InN dot height is about 10 nm, which is much smaller than the wire diameter with around 30 nm. It is also show that the InN/InGaN dots aligned along growth direction of the GaN NRs. Fig. 1(b) and (c) show sharp and isolated single exciton emission line in the near IR spectral range (1131 nm) was observed. Radiative and nonradiative lifetimes are also measured in the NRs by time resolved PL measurements. The experimental results are comparable with the data obtained by numerical simulation(by APSYS (CROSS-LIGHT)) of near IR emission. Based on the experimental data, we will present a schematic model of the InN/InGaN NRs formation and the probability of application of light emitting diode and single photon light source for the optical communication.

Fig. 1. (a) TEM images of the active region of an InN/InGaN/GaN dot-in-a-nanorods heterostructures. The (b) and (c) show the micro-photoluminescence on the InN/InGaN/GaN dot-in-a-nanorods heterostructures.