We discuss optical data obtained on (InAs/GaAs)‐InGaAlAs multiquantum well structures grown by molecular beam epitaxy. The combined use of photoluminescence and photoluminescence excitation to study such structures is an efficient test of the quality of the highly strained InAs/GaAs ordered alloy, which is used as the well material. The electron effective mass and the lifting of the valence‐band degeneracy in InAs/GaAs short‐period superlattices are obtained experimentally for the first time.