Silicon-based electro-optic modulators for linear and nonlinear radio-over-fiber applications

The potential of silicon-based electro-optic modulators for enabling high performance radio-over-fiber applications is demonstrated. Two different applications taking advantage of the linear and nonlinear regime of silicon modulators are investigated. A ring-assisted Mach-Zehnder modulator (MZM) is firstly investigated for RF analog transmission. QPSK and 16-QAM electrical signals are modulated on a 1 GHz RF carrier with an error vector magnitude lower than 10% for a symbol rate of 20Msymbols/s. A MZM enhanced via slow-light propagation is secondly investigated for photonic mixing applications. A 10Msymbol/s QPSK signal at 1GHz RF frequency is successfully up-converted to 10.25GHz with low conversion losses ~7dB.