Electronic structure and optical properties of TaNO: An ab initio study

Area of Science:

• Materials Science
• Condensed Matter Physics
• Computational Chemistry

Background:

• Understanding the optoelectronic properties of novel materials is crucial for advancing electronic devices.
• Tantalum niobium oxide (TaNO) is a material with potential applications in optoelectronics.
• Investigating different phases of TaNO can reveal unique material characteristics.

Purpose of the Study:

• To investigate the structural and optoelectronic properties of simple and slab phase TaNO.
• To determine the band structure, electronic properties, and interband transitions of TaNO.
• To assess the suitability of TaNO for optoelectronic applications.

Main Methods:

• Ab initio calculations using density functional theory (DFT).
• Full potential augmented plane wave (FP-LAPW) method implemented in Wien 2k.
• Modified Becke-Johnson potential (mBJ-GGA) for accurate electronic structure calculations.

Main Results:

• Simple TaNO exhibits an indirect bandgap of 3.2 eV, while slab TaNO shows a direct bandgap of 1.5 eV.
• Interband electronic transitions were identified, linked to specific orbital contributions (Ta-p, N-p/s, O-p).
• Plasmon energy was found to be approximately 10 eV, with static dielectric constant and refraction values aligning with experimental data.

Conclusions:

• Slab TaNO possesses a direct bandgap, indicating superior optoelectronic properties compared to simple TaNO.
• The calculated properties suggest that slab TaNO is a promising candidate for optoelectronic applications.
• DFT calculations provide valuable insights into the electronic and optical behavior of TaNO phases.