Phase-sensitive frequency conversion of quadrature modulated signals

Optics Express (Impact Factor: 3.49). 05/2013; 21(10):12713-27. DOI: 10.1364/OE.21.012713
Source: PubMed


Two mechanisms that can make frequency conversion based on nonlinear mixing dependent on the phase of the input signal are identified. A novel phase-to-polarization converter that converts the orthogonal phase components of an input signal to two orthogonally polarized outputs is proposed. The operation of this scheme and a previously reported scheme at an increased symbol rate are simulated with semiconductor optical amplifiers (SOAs) as the nonlinear devices. Experimental results demonstrate the effectiveness of SOAs for nonlinear mixing over a wide range of wavelengths and difference frequencies and confirm the accuracy of the numerical model.

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    • "In spite of the operation of the scheme having been numerically predicted at a symbol rate as high as 40 Gbaud, and positive conversion efficiencies having been reported with pump spacings of 600 GHz [8], pattern effects need to be addressed when processing high bit rate signals in SOAs, due to a relatively slow carrier recovery time. To fully exploit the benefits of all-optical signal processing, bit rate transparent operation is a desirable condition. "
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