Charge transfer along localized states in InSe and InSe⟨Sn⟩ single crystals

Abstract

It is established that at temperatures T<200K hopping conductivity with variable hopping length exists across natural layers of undoped and doped (0.2 and 0.4at% Sn) InSe single crystals in a constant electric field. The density of states near the Fermi level (NF=5.36⋅1018–1.72⋅1019eV−1⋅cm−3), the energy spread of the states (ΔE=0.028–0.040eV), the localization radius (a=58Å), and the average hopping length (Rav=99.5–130Å) in the temperature interval 100–200K are evaluated.