skip to main content


Title: Effect of Titanium Induced Chemical Inhomogeneity on Crystal Structure, Electronic Structure, and Optical Properties of Wide Band Gap Ga 2 O 3
Award ID(s):
1827745
PAR ID:
10160694
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Crystal Growth & Design
Volume:
20
Issue:
3
ISSN:
1528-7483
Page Range / eLocation ID:
1422 to 1433
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. The search for new wide-band-gap materials is intensifying to satisfy the need for more advanced and energy-efficient power electronic devices. Ga2O3 has emerged as an alternative to SiC and GaN, sparking a renewed interest in its fundamental properties beyond the main β-phase. Here, three polymorphs of Ga2O3, α, β, and ε, are investigated using X-ray diffraction, X-ray photoelectron and absorption spectroscopy, and ab initio theoretical approaches to gain insights into their structure–electronic structure relationships. Valence and conduction electronic structure as well as semicore and core states are probed, providing a complete picture of the influence of local coordination environments on the electronic structure. State-of-the-art electronic structure theory, including all-electron density functional theory and many-body perturbation theory, provides detailed understanding of the spectroscopic results. The calculated spectra provide very accurate descriptions of all experimental spectra and additionally illuminate the origin of observed spectral features. This work provides a strong basis for the exploration of the Ga2O3 polymorphs as materials at the heart of future electronic device generations. 
    more » « less
  2. Half-metallic Heusler alloys have attracted significant attention due to their potential application in spin-transport-based devices. We have synthesized one such alloy, CoFeV 0.5 Mn 0.5 Si, using arc melting and high-vacuum annealing at 600 °C for 24 hours. First principles calculation indicates that CoFeV 0.5 Mn 0.5 Si shows a nearly half-metallic band structure with a degree of spin polarization of about 93%. In addition, this value can be enhanced by the application of tensile strain. The room temperature x-ray diffraction patterns are indexed with the cubic crystal structure without secondary phases. The annealed sample shows ferromagnetic order with the Curie temperature well above room temperature ( T c = 657 K) and a saturation magnetization of about 92 emu/g. Our results indicate that CoFeV 0.5 Mn 0.5 Si has a potential for room temperature spin-transport-based devices. 
    more » « less