We present a theoretical study of the electronic structure and optical properties of free-standing GaN and AlN nanowires. We have implemented the empirical tight-binding method, with an orbital basis sp(3), that includes the spin-orbit interaction. The passivation of the dangling bonds at the free surfaces is also studied, together with the effects on the electronic structure of the nanowire. For both GaN and AlN nanowires, we have found a remarkable anisotropy of the optical absorption when the light-polarization changes, showing in the case of GaN a dependence on the nanowire size.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1088/0953-8984/24/29/295301 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Improvement of the Thermal Performance of the GaN-on-Si Microwave High-Electron-Mobility Transistors by Introducing a GaN-on-Insulator Structure.
Micromachines (Basel)
December 2024
School of Microelectronics, Xidian University, Xi'an 710071, China.
GaN-on-Si high-electron-mobility transistors have emerged as the next generation of high-powered and cost-effective microwave devices; however, the limited thermal conductivity of the Si substrate prevents the realization of their potential. In this paper, a GaN-on-insulator (GNOI) structure is proposed to enhance the heat dissipation ability of a GaN-on-Si HEMT. Electrothermal simulation was carried out to analyze the thermal performance of the GNOI-on-Si HEMTs with different insulator dielectrics, including SiO, SiC, AlN, and diamond.
View Article and Find Full Text PDFThe effect of interface polarity on the basal dislocations at the GaN/AlN interface.
Phys Chem Chem Phys
December 2024
Advanced Research Institute of Multidisciplinary Sciences, Qufu Normal University, Qufu, Shandong Province, 273165, China.
Article Synopsis
- High-density dislocations in GaN negatively impact the performance of GaN-based devices, with current research mostly focusing on threading dislocations in bulk crystals.
- This study shifts the focus to basal dislocations, which have been observed experimentally but are less understood.
- Findings suggest that growing GaN on N-polar AlN at 1900 K enhances the crystal quality by increasing wurtzite structure content and reducing dislocation density.
Phonon Screening of Excitons in Atomically Thin Semiconductors.
Phys Rev Lett
November 2024
Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA.
Atomically thin semiconductors, encompassing both 2D materials and quantum wells, exhibit a pronounced enhancement of excitonic effects due to geometric confinement. Consequently, these materials have become foundational platforms for the exploration and utilization of excitons. Recent ab initio studies have demonstrated that phonons can substantially screen electron-hole interactions in bulk semiconductors and strongly modify the properties of excitons.
View Article and Find Full Text PDFTheoretical study of the temperature dependence of Auger-Meitner recombination in (Al,Ga)N quantum wells.
J Phys Condens Matter
December 2024
Tyndall National Institute, University College Cork, Cork T12 R5CP, Ireland.
Article Synopsis
- Non-radiative Auger-Meitner recombination processes in III-nitride optoelectronic devices can lead to efficiency drops at high temperatures and carrier densities, but understanding of these processes in UV-operating devices is limited.
- The study investigates the temperature dependence of Auger-Meitner recombination in (Al,Ga)N/AlN quantum wells using a model that considers alloy fluctuations and carrier localization effects.
- Results indicate that while radiative recombination slightly increases with temperature, Auger-Meitner recombination may decrease, suggesting that other non-radiative processes outside the active region are likely responsible for the thermal efficiency drop in these devices.
Color-tunable micro-scale light-emitting diodes (Micro-LEDs) can achieve full-color display in a simple and low-cost way. In this paper, we demonstrate growth of three-dimensional (3D) inverted pyramid GaN on nano-patterned sapphire substrates (NPSS). By using the sputtered AlN nucleation layer, the uniformity of the inverted pyramid has been improved to a large extent.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!