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arXiv · 1112.5140

Second-harmonic generation induced by electric currents in GaAs

Brian A. Ruzicka·Lalani K. Werake·Guowei Xu·Jacob B. Khurgin·E. Ya. Sherman·Judy Z. Wu·Hui Zhao
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Abstract

We demonstrate a new, nonlinear optical effect of electric currents. First, a steady current is generated by applying a voltage on a doped GaAs crystal. We demonstrate that this current induces second-harmonic generation of a probe laser pulse. Second, we optically inject a transient current in an undoped GaAs crystal by using a pair of ultrafast laser pulses, and demonstrate that it induces the same second-harmonic generation. In both cases, the induced second-order nonlinear susceptibility is proportional to the current density. This effect can be used for nondestructive, noninvasive, and ultrafast imaging of currents. These advantages are illustrated by the real-time observations of a coherent plasma oscillation and spatial resolution of current distribution in a device. This new effect also provides a mechanism for electrical control of the optical response of materials.

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Brian A. Ruzicka, Lalani K. Werake, Guowei Xu, Jacob B. Khurgin, E. Ya. Sherman, Judy Z. Wu, Hui Zhao. 2011-12-21. Second-harmonic generation induced by electric currents in GaAs. https://doi.org/10.1103/physrevlett.108.077403

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