ALTERNATING BE AND C DOPING FOR STRAIN COMPENSATED GAAS ALAS DISTRIBUTED BRAGG REFLECTORS/

We demonstrate a new type of strain compensated, p-type distributed Br agg reflector (DBR) using alternating doping of Be in GaAs and C in Al As with carbon concentrations as high as 2x10(20) Cm-3. These DBRs exh ibit simultaneously a high crystalline quality, an excellent surface m orphology, and no misfit dislocations, which cannot be achieved in und oped or Be-doped DBRs. The absolute optical reflectivity is as high as in the undoped DBR. The differential resistance of these structures i s comparable to best reported values in Be-doped DBRs. (C) 1997 Americ an Institute of Physics.