We demonstrate an undoped 20 1/2 pair AlAsSb/GaAsSb distributed Bragg reflector (DBR) grown lattice matched to an InP substrate by molecular beam epitaxy. Reflectivity measurements indicate a stop band centered at 1.78 &mgr;m with a maximum reflectivity exceeding 99%. We also measure current–voltage characteristics in a similar 10 1/2 periodp‐type DBR and find that a current density of 1kA/cm2produces a 2.5 V drop. Hole mobilities and doping concentrations in AlAsSb and GaAsSb are also reported. ©1995 American Institute of Physics.