Mid-infrared optical parametric amplifier using silicon nanophotonic waveguides
Abstract
All-optical signal processing is an approach used to dramatically decrease power consumption and speed up the performance of next-generation optical telecommunications networks. Nonlinear optical effects such as four-wave mixing and parametric gain have been explored to realize all-optical functions in glass fibres. An alternative approach is to use nanoscale engineering of silicon waveguides to enhance optical nonlinearities by up to five orders of magnitude, enabling integrated chip-scale all-optical signal processing. Four-wave mixing within silicon nanophotonic waveguides has been used to demonstrate telecom-band (λ ~ 1,550 nm) all-optical functions including wavelength conversion, signal regeneration and tunable optical delay. Despite these important advances, strong two-photon absorption of the telecom-band pump presents a fundamental obstacle, limiting parametric gain to values of several decibels. Here, we demonstrate a silicon nanophotonic optical parametric amplifier exhibiting broadband gain as high as 25.4 dB, using a mid-infrared pump near one-half the bandgap energy (E ~ 0.55 eV, λ ~ 2,200 nm), where parasitic two-photon absorption-related absorption vanishes. This gain is high enough to compensate all insertion losses, resulting in 13-dB net off-chip amplification, using only an ultra-compact 4-mm silicon chip. Furthermore, engineering of higher-order waveguide dispersion can potentially enable mid-infrared-pumped silicon parametric oscillators and amplifiers for telecom-band optical signals.
- Publication:
-
Nature Photonics
- Pub Date:
- August 2010
- DOI:
- 10.1038/nphoton.2010.119
- arXiv:
- arXiv:1001.1533
- Bibcode:
- 2010NaPho...4..557L
- Keywords:
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- Physics - Optics
- E-Print:
- doi:10.1038/nphoton.2010.119