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arXiv · 1302.4633

All-optically induced currents resulting from frequency modulated coherent polarization

Shekhar Priyadarshi·Klaus Pierz·Mark Bieler
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Abstract

We employ polarization-shaped ultrafast optical pulses to generate photocurrents which only arise if the optically induced coherent polarization is frequency modulated. This frequency modulation is obtained via detuned excitation of light-hole excitons in (110)-oriented GaAs quantum wells. The observed photocurrents vanish for resonant excitation of excitons and reverse their direction with a change of the sign of detuning. Moreover, the currents do not exist for continuous-wave excitation. Our work reveals the existence of a new class of photocurrents and visualizes the complexity of current response tensors. This is helpful for the better understanding of optically induced microscopic transport in semiconductors.

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Shekhar Priyadarshi, Klaus Pierz, Mark Bieler. 2013-02-19. All-optically induced currents resulting from frequency modulated coherent polarization. https://doi.org/10.1063/1.4795722

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