We report the design, growth, and characterization of an InAlP/InGaP strain‐modulated aperiodic superlattice heterobarrier (SMASH) for the enhancement of the performance of visible light‐emitting devices. These InAlP/InGaP heterostructures are grown on GaAs substrates by low‐pressure metalorganic chemical vapor deposition. Electron‐wave reflectivity calculations show that the virtual confining potential energy for conduction‐band electrons at the InAlP/InGaP interface can be increased by up to ∼660 meV by employing this novel barrier. Significant improvements in photoluminescence intensity at 300 and 4.2 K are observed from both InGaP quantum well and InGaP bulk‐layer double heterostructures utilizing the SMASH structure. ©1995 American Institute of Physics.