Photoreflectance investigation of hydrogenated (InGa)(AsN)/GaAs heterostructures M. Geddo, R. Pezzuto, M. Capizzi, A. Polimeni, D. Gollub, M. Fischer and A. Forchel Eur. Phys. J. B, 30 1 (2002) 39-43 Published online: 19 November 2002 DOI: 10.1140/epjb/e2002-00355-x