Ultracompact all-optical XOR logic gate in a slow-light silicon photonic crystal waveguide

C. Husko, T. D. Vo, B. Corcoran, J. Li, T. F. Krauss, B. J. Eggleton

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75 Citations (Scopus)


We demonstrate an ultracompact, chip-based, all-optical exclusive-OR (XOR) logic gate via slow-light enhanced four-wave mixing (FWM) in a silicon photonic crystal waveguide (PhCWG). We achieve error-free operation (<10−9) for 40 Gbit/s differential phase-shift keying (DPSK) signals with a 2.8 dB power penalty. Slowing the light to vg = c/32 enables a FWM conversion efficiency, η, of -30 dB for a 396 μm device. The nonlinear FWM process is enhanced by 20 dB compared to a relatively fast mode of vg = c/5. The XOR operation requires ≈ 41 mW, corresponding to a switching energy of 1 pJ/bit. We compare the slow-light PhCWG device performance with experimentally demonstrated XOR DPSK logic gates in other platforms and discuss scaling the device operation to higher bit-rates. The ultracompact structure suggests the potential for device integration.
Original languageEnglish
Pages (from-to)20681-20690
Number of pages10
JournalOptics Express
Issue number21
Publication statusPublished - 2011
Externally publishedYes

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