Oxygen and potassium vacancies in KTP calculated from first principles.
J Phys Condens Matter
; 31(38): 385401, 2019 Sep 25.
Article
em En
| MEDLINE
| ID: mdl-31189148
ABSTRACT
The atomic geometry and energetics of oxygen and potassium vacancies in potassium titanyl phosphate (KTP) as well as their electronic and optical properties are studied within density-functional theory in dependence of their charge state. Oxygen vacancies formed between Ti and P are characterized by a negative-U behavior. Their neutral charge state is favored for Fermi levels near the conduction band and gives rise to a defect level in the band gap, which leads to an additional optical absorption peak. In contrast, the two-fold positive charge state, stable for low and intermediate values of the Fermi level, modifies the KTP optical response only slightly. Oxygen vacancies formed between two Ti atoms are two-fold positively charged, while potassium vacancies are negatively charged irrespective of the Fermi level position. In both these cases, the KTP optical response is essentially not affected.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
J Phys Condens Matter
Assunto da revista:
BIOFISICA
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Alemanha
País de publicação:
ENGLAND
/
ESCOCIA
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GB
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GREAT BRITAIN
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INGLATERRA
/
REINO UNIDO
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SCOTLAND
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UK
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UNITED KINGDOM