Photothermal investigations of doping effects on opto-thermal properties of bulk GaSb

GaSb is a direct gap semiconductor (0.72 ev) having good carriers motility and significant electro-optical potential in the near IR range. As substrate or active layer, GaSb can be employed in conjunction with many semiconductors such as (AlGa)Sb or In(AsSb) and has interesting hetero junction potential for detectors, lasers and quantum well structures. The aim of this work is to investigate the influence of doping on the opto-thermal properties (optical absorption, refractive index and thermal diffusivity) of doped and undoped GaSb bulk throw, the phothermal deflection and spectroscopic reflectivity. It is found that absorption below the gap and thermal diffusivity increases with doping concentration. (C) 2009 Elsevier B.V. All rights reserved.