Direct observation of tunnelled intergrowth in SnO ₂ /Ga ₂ O ₃ complex nanowires

Abstract β -Ga ₂ O ₃ intergrowths have been revealed in the SnO ₂ rutile structure when SnO ₂ /Ga ₂ O ₃ complex nanostructures are grown by thermal evaporation with a catalyst-free basis method. The structure is formed by a Ga ₂ O ₃ nanowire trunk, around which a rutile SnO ₂ particle is formed with [001] aligned to the [010] Ga ₂ O ₃ trunk axis. Inside the SnO ₂ particle, β -Ga ₂ O ₃ units occur separated periodically by hexagonal tunnels in the (210) rutile plane. Orange (620 nm) optical emission from tin oxide, with a narrow linewidth indicating localised electronic states, may be associated with this β -Ga ₂ O ₃ intergrowth.