Exciton-polaron formation in GaGdN/AlGaN multiquantum wells was inferred from the lower
energy of the photoluminescence peak observed for the GaGdN quantum wells (QWs)
compared with GaN QWs. The rather low value of the excitonic transition energy is attributed
to exciton-polarons bound to the Gd ions. Exciton-polarons are most likely to occur due to the
lattice distortion around the substituted Gd ions in addition to the exchange interaction between
Gd3+ magnetic ions and the strongly confined charge carrier spins in GaGdN QWs. The
mechanism of exciton-polaron formation is discussed. The magnetic behavior is briefly
presented.