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arXiv · 0812.4046

Terahertz Bloch oscillator with a modulated bias

Timo Hyart·Natalia V. Alexeeva·Jussi Mattas·Kirill N. Alekseev
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Abstract

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 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.

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Timo Hyart, Natalia V. Alexeeva, Jussi Mattas, Kirill N. Alekseev. 2008-12-21. Terahertz Bloch oscillator with a modulated bias. https://doi.org/10.1103/physrevlett.102.140405

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