Klappenberger, F and Ignatov, A. A. and Winnerl, S. and Schomburg, Ekkehard and Wegscheider, Werner and Renk, Karl Friedrich and Bichler, Max
Broadband semiconductor superlattice detector for THz radiation.
Applied Physics Letters 78 (12), pp. 1673-1675.
We report on a broadband GaAs/AlAs superlattice detector for THz radiation; a THz field reduces the current through a superlattice, which is carried by miniband electrons, due to modulation of the Bloch oscillations of the miniband electrons. We studied the detector response, by use of a free electron laser, in a large frequency range (5–12 THz). The responsivity showed strong minima at frequencies of infrared active phonons of the superlattice. A theoretical analysis of the detector delivers an understanding of the role of phonons and gives a characterization of the responsivity.