RESONANT RAMAN SCATTERING IN GaSb-AlSb SUPERLATTICES.

The electronic properties of GaSb-AlSb superlattices (SL) have been recently analyzed by different experimental techniques showing unambiguously the formation of electronic subbands at the GAMMA -point. To our knowledge, the only reported information on the band structure away from the Brillouin zone center is supplied by electroreflectance measurements. They show some features probably related to E//1 and E//1 plus DELTA //1 transitions at the bulk materials. In this communication we analyze the electronic structure of GaSb-AlSb SL associated with the E//1 transition of GaSb by resonant Raman scattering. The studied samples are a GaSb single crystal and two SL grown on (001)GaSb substrates. The first SL has 65 periods, each containing 26 layers of GaSb and 20 of AlSb. The second SL has 45 periods each one with 52 layers of GaSb and 20 of AlSb.