Abstract: The invention relates to a photoconductor for emitting and/or receiving electromagnetic waves, comprising a material region (1) comprising a first and a second section (A, C), wherein the second section (C) provides a higher density of charge carrier trapping centers and/or recombination centers than the first section (A), a confinement generating a sub-band structure of the charge carrier energy states in the material region (1), wherein the first and the second section (A,C) are arranged and configured in such a manner that a maximum of the carrier probability density (P1) of the sub-band ground state is located in one of these sections (A, C) and a maximum of the carrier probability density (P2) of an excited sub-band state is located in the respective other section.