We have investigated the effect of a brief As-2-soak at the GaSb surface on the nature of the InAs-on-GaSb interface. We find that As-2 efficiently removes Sb from GaSb and that a controlled As-2-soak may be a necessary step in forming a "GaAs-like" interface without structural or optical degradation. We observe that the thickness of the "GaAs-like" interfacial layer and the band-edge transition wavelength in InAs/GaSb superlattices both increase with increasing As-2-soak duration. Published by Elsevier Science B.V.