Normal incidence intersubband optical transition in GaSb/InAs superlattices

A novel intersubband optical transition, incorporating interband and p-type intersubband optical transition mechanisms, in a suitably designed GaSb/InAs superlattice is proposed. Such a structure utilizes the strong mixing of GaSb light-hole band with InAs conduction band and the heavy-hole to light-hole intervalence-subband transition in the GaSb/InAs superlattice to obtain a strong normal incidence photoabsorption coefficient (over 8.0×104 cm−1) at a wavelength near 10 μm.