Temperature and compositional behaviour of electrical conductivity and optical absorption edge in Cu sub(7)Ge(S sub(1 - x)Se sub(x)) sub(5)I mixed superionic crystals

• Published in: Solid state ionics Vol. 181; no. 35-36; pp. 1596 - 1600
• Main Authors: Studenyak, I P, Kranjcec, M, Bilanchuk, V V, Kokhan, O P, Orliukas, A F, Kezionis, A, Kazakevicius, E, Salkus, T
• Format: Journal Article
• Language: English
• Published: 09.11.2010
• Subjects: Electrical conductivity; Electrical resistivity; Mixed crystals; Optical data processing; Optical properties; Resistivity; Vapour
• ISSN: 0167-2738
• DOI: 10.1016/j.ssi.2010.09.021

Electrical and optical properties of Cu sub(7)Ge(S sub(1 - x)Se sub(x)) sub(5)I mixed crystals, grown by chemical vapour transport, are studied. Compositional dependencies of their electrical conductivity, measured in the frequency range 1.0 [inline image] 10 super(6)-1.2 [inline image] 10 super(9) Hz at 100-300 K and the corresponding activation energy, are analysed. The optical absorption edge of Cu sub(7)Ge(S sub(1 - x)Se sub(x)) sub(5)I mixed crystals is studied in the temperature range 77-300 K, the compositional dependencies of the optical pseudogap and Urbach energy being obtained. The effect of different types of disordering on the optical absorption processes at S --> Se anionic substitution in the Cu sub(7)Ge(S sub(1 - x)Se sub(x)) sub(5)I mixed crystals is investigated.