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arXiv · 1604.03732

Sub-cycle control of terahertz high-harmonic generation by dynamical Bloch oscillations

O. Schubert·M. Hohenleutner·F. Langer·B. Urbanek·C. Lange·U. Huttner·D. Golde·T. Meier·M. Kira·S. W. Koch·R. Huber
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Abstract

Ultrafast charge transport in strongly biased semiconductors is at the heart of highspeed electronics, electro-optics, and fundamental solid-state physics. Intense light pulses in the terahertz (THz) spectral range have opened fascinating vistas: Since THz photon energies are far below typical electronic interband resonances, a stable electromagnetic waveform may serve as a precisely adjustable bias. Novel quantum phenomena have been anticipated for THz amplitudes reaching atomic field strengths. We exploit controlled THz waveforms with peak fields of 72 MV/cm to drive coherent interband polarization combined with dynamical Bloch oscillations in semiconducting gallium selenide. These dynamics entail the emission of phase-stable high-harmonic transients, covering the entire THz-to-visible spectral domain between 0.1 and 675 THz. Quantum interference of different ionization paths of accelerated charge carriers is controlled via the waveform of the driving field and explained by a quantum theory of inter- and intraband dynamics. Our results pave the way towards all-coherent THz-rate electronics.

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O. Schubert, M. Hohenleutner, F. Langer, B. Urbanek, C. Lange, U. Huttner, D. Golde, T. Meier, M. Kira, S. W. Koch, R. Huber. 2016-04-13. Sub-cycle control of terahertz high-harmonic generation by dynamical Bloch oscillations. https://doi.org/10.1038/nphoton.2013.349

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