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Plasma optical modulators for intense lasers.

ABSTRACT: Optical modulators can have high modulation speed and broad bandwidth, while being compact. However, these optical modulators usually work for low-intensity light beams. Here we present an ultrafast, plasma-based optical modulator, which can directly modulate high-power lasers with intensity up to 10(16)?W?cm(-2) to produce an extremely broad spectrum with a fractional bandwidth over 100%, extending to the mid-infrared regime in the low-frequency side. This concept relies on two co-propagating laser pulses in a sub-millimetre-scale underdense plasma, where a drive laser pulse first excites an electron plasma wave in its wake while a following carrier laser pulse is modulated by the plasma wave. The laser and plasma parameters suitable for the modulator to work are based on numerical simulations.

SUBMITTER: Yu LL

PROVIDER: S-EPMC4906397 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

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Plasma optical modulators for intense lasers.

Yu Lu-Le LL Zhao Yao Y Qian Lie-Jia LJ Chen Min M Weng Su-Ming SM Sheng Zheng-Ming ZM Jaroszynski D A DA Mori W B WB Zhang Jie J

Nature communications 20160610

Optical modulators can have high modulation speed and broad bandwidth, while being compact. However, these optical modulators usually work for low-intensity light beams. Here we present an ultrafast, plasma-based optical modulator, which can directly modulate high-power lasers with intensity up to 10(16) W cm(-2) to produce an extremely broad spectrum with a fractional bandwidth over 100%, extending to the mid-infrared regime in the low-frequency side. This concept relies on two co-propagating l ...[more]

PMID: 27283369

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