We measured the time-resolved transmission of picosecond terahertz pulses through a modulation-doped Al(0.3)Ga(0.7)As/GaAs heterojunction in the presence of a D.C. current. The introduction of a current changes the transmission on the order of one percent and causes additional dispersion. This effect can be explained by a drift-velocity-shifted Fer...
We present a concept and possible applications of asymmetrically-shaped diodes fabricated from different types of semiconductors, i.e. non-uniform GaAs, n-Si and modulation-doped GaAs/Al(0.25)Ga(0.75)As structures. The devices can be used to detect electromagnetic radiation within a very-broad frequency band ranging from 10 GHz up to 2.5 THz (non-u...
Bauer, T.Hummel, A.B.Kolb, J.S.Roskos, H.G.Kosevich, Y.Köhler, K.
Terahertz-emission spectroscopy reveals two regimes of the Hall current of impulsively excited coherent charge-carrier wavepackets in a GaAs/AlGaAs superlattice as a function of the electric and magnetic bias fields.
Bauer, T.Kolb, J.S.Hummel, A.B.Roskos, H.G.Kosevich, Y.Köhler, K.
The Coherent Hall Effect denotes the transient current/voltage Hall response of impulsively excited coherent charge-carrier wavepackets in a solid. We studied this effect by THz-emission spectroscopy on a semiconductor superlattice in crossed electric and magnetic fields. Depending on the relative magnetic field strength, two regimes of coherent os...