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arXiv · 2010.12424

Optical Push Broom On a Chip

Mahmoud A. Gaafar·He Li·Xinlun Cai·Juntao Li·Manfred Eich·Alexander Yu. Petrov
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Abstract

Here we report the first experimental demonstration of light trapping by a refractive index front in a silicon waveguide, the optical push broom effect. The front generated by a fast pump pulse collects and traps the energy of a CW signal with smaller group velocity and tuned near to the band gap of the Bragg grating introduced in the waveguide. This situation represents an optical analogue of light trapping in a tapered plasmonic waveguide where light is stopped without reflection. The energy of the CW signal is accumulated inside the front and distributed in frequency. In this experiment a 2 ps free carrier front was generated via two photon absorption of the pump in silicon waveguide. It collects approximately a 30 ps long packet of the CW signal. The presented effect can be utilized to compress signals in time and space.

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Mahmoud A. Gaafar, He Li, Xinlun Cai, Juntao Li, Manfred Eich, Alexander Yu. Petrov. 2020-10-23. Optical Push Broom On a Chip. https://arxiv.org/abs/2010.12424

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