Terahertz Bloch oscillator with a modulated bias
journal contributionposted on 24.07.2013, 12:35 by Timo Hyart, Natalia V. Alexeeva, Jussi Mattas, Kirill Alekseev
Electrons performing Bloch oscillations in an energy band of a dc-biased superlattice in the presence of weak dissipation can potentially generate THz fields at room temperature. The realization of such a Bloch oscillator is a long-standing problem due to the instability of a homogeneous electric field in conditions of negative differential conductivity. We establish the theoretical feasibility of stable THz gain in a long superlattice device in which the bias is quasistatically modulated by microwave fields. The modulation waveforms must have at least two harmonics in their spectra.