Thickness-tunable band gap modulation in γ-In2Se3

Abstract

We have grown γ-phase layered In₂Se₃ crystals with various thicknesses from hundreds of nm to hundreds of μm. The as-grown layers showed different crystal colors from light yellow to dark red owing to their different thicknesses. The direct band edge of γ-In₂Se₃ has been probed by transmittance and thermoreflectance measurements at room temperature. An amorphous effect mainly dominates the thickness-dependent band gap changes of the selenide.