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arXiv · 0810.1939

Inverse Raman Scattering in Silicon

D. R. Solli·P. Koonath·B. Jalali
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Abstract

Stimulated Raman scattering is a well-known nonlinear process that can be harnessed to produce optical gain in a wide variety of media. This effect has been used to produce the first silicon-based lasers and high-gain amplifiers. Interestingly, the Raman effect can also produce intensity-dependent nonlinear loss through a corollary process known as inverse Raman scattering (IRS). Here, we demonstrate IRS in silicon--a process that is substantially modified by the presence of optically-generated free carriers--achieving attenuation levels >15 dB with a pump intensity of 4 GW/cm^2. Ironically, we find that free-carrier absorption, the detrimental effect that suppresses other nonlinear effects in silicon, actually facilitates IRS by delaying the onset of contamination from coherent anti-Stokes Raman scattering. The carriers allow significant IRS attenuation over a wide intensity range. Silicon-based IRS could be used to produce chip-scale wavelength-division multiplexers, optical signal inverters, and fast optical switches.

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D. R. Solli, P. Koonath, B. Jalali. 2008-10-10. Inverse Raman Scattering in Silicon. https://arxiv.org/abs/0810.1939

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