GaGdN/AlGaN multiple quantum disks grown by RF‐plasma‐assisted molecular‐beam epitaxy

Abstract

III-V-based diluted magnetic semiconductor (DMS) GaGdN/ AlGaN multiple quantum disks (MQDisks) were fabricated on Si (001) substrates with native silicon oxides by RF-plasmaassisted molecular-beam epitaxy (RF-MBE). It was found that the degree of the c-axis orientation of GaGdN/AlGaN MQDisks and the Ga atomic configuration around Gd atom were improved due to the growth of AlGaN disks, comparing with the GaGdN nanorods grown without AlGaN disks. Additionally, GaGdN/AlGaN MQDisks showed larger saturation magnetisation than that of the GaGdN nanorods. With increasing the height of AlGaN disk, saturation magnetisation was increased.

Structural and Optical Characterization of GaN/AlGaN Single Quantum Disk Nanorods

“…Broken-ring RHEED patterns were observed indicating that the hexagonal--GaN layers were grown with their c-axes perpendicular to the substrate surfaces [10]. No formation of pure metal droplets on the surfaces during growth is detected.…”

“…However, the size distribution of the nanorods makes it dicult to analyze accurately their optical properties. Nano columnar heterostructures including quantum disks (QDisks) bring the new eects ensuing from quantum connement eects in the columnar geometry [9,10]. The typical diameter of IIIN nanowires grown by the plasma-assisted molecular beam epitaxy (PAMBE) techniques is in the 2050 nm range, which is large compared to the GaN Bohr radius 3 nm.…”