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Ba_{2}TeO as an optoelectronic material: First-principles study

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 نشر من قبل Jifeng Sun
 تاريخ النشر 2015
  مجال البحث فيزياء
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The band structure, optical and defects properties of Ba_{2}TeO are systematically investigated using density functional theory with a view to understanding its potential as an optoelectronic or trans- parent conducting material. Ba_{2}TeO crystallizes with tetragonal structure (space group P4/nmm) and with a 2.93 eV optical band gap 1 . We find relatively modest band masses for both electrons and holes suggesting applications. Optical properties show a infrared-red absorption when doped. This could potentially be useful for combining wavelength filtering and transparent conducting functions. Furthermore, our defect calculations show that Ba_{2}TeO is intrinsically p-type conducting under Ba-poor condition. However, the spontaneous formation of the donor defects may constrain the p-type transport properties and would need to be addressed to enable applications.



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