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Updated: Jul 31, 2025
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Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures
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Influence of native defects on magneto-optoelectronic properties ofα-MoO3
Poonam Sharma1, Vikash Mishra1, Alok Shukla1
1Department of Physics, Indian Institute of Technology Bombay, Mumbai 400076, India.
Summary
Native defects in semiconducting alpha-molybdenum trioxide (α-MoO3) significantly alter its properties. Oxygen and Mo-O vacancies create mid-gap states, inducing half-metallic behavior and magnetic moments, crucial for spintronic devices.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Solid State Chemistry
Background:
- Semiconducting oxides exhibit diverse electronic, optical, and magnetic properties.
- Native defects critically influence these properties in materials like α-MoO3.
Purpose of the Study:
- Investigate the impact of native defects on the properties of α-MoO3.
- Understand how vacancies influence magneto-optoelectronic characteristics.
Main Methods:
- First-principles density functional theory (DFT) calculations.
- Formation energy calculations to determine defect stability.
- Ab initio molecular dynamics simulations for room temperature stability.
Main Results:
- Oxygen and Mo-O vacancies are energetically favorable over Mo vacancies.
- Vacancies introduce mid-gap states affecting magneto-optoelectronic properties.
- Single Mo vacancy induces half-metallic behavior and a large magnetic moment (5.98μB).
- Single O vacancy closes the band gap, remaining non-magnetic.
- Mo-O co-vacancies reduce the band gap and induce a magnetic moment (2.0μB).
- Absorption spectra show unique peaks for Mo and O vacancies.
Conclusions:
- Defect engineering in α-MoO3 can tune its magneto-optoelectronic properties.
- Induced magnetic moments are stable at room temperature.
- Findings support the design of advanced magneto-optoelectronic and spintronic devices.
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