We demonstrate four-wave mixing (FWM) in a 10-μm-radius silicon microring resonator with the assistance of giant nonlinearity of the monolayer graphene. A maximum enhancement of 6.8 dB of conversion efficiency in the silicon-graphene microring (SGM) resonator is observed. A nonlinear propagation model is established and the optical Kerr coefficient of the silicon-graphene hybrid waveguide is three times larger than that of the silicon waveguide.

We fabricate a nonlinear optical device based on graphene-silicon microring resonator (GSMR). Using such graphene-assisted nonlinear optical device, we experimentally demonstrate up and down wavelength conversion of a 10-Gbaud quadrature phase-shift keying (QPSK) signal by exploiting degenerate four-wave mixing (FWM) progress in the fabricated GSMR. We study the conversion efficiency as a function of the pump power. In addition, the resonant wavelength of GSMR is tuned by changing the temperature from 20°C to 40°C. We evaluate the bit-error rate (BER) performance for up and down wavelength conversion. The observed optical signal-to-noise ratio (OSNR) penalties for QPSK up and down wavelength conversion are less than 1.4 dB at a BER of 1 × 10^-3. The BER performance as a function of the pump power for up wavelength conversion is also assessed. The minimum OSNR penalty is less than 0.8 dB when the pump power is 13.3 dBm.

Compact and flexible all-optical signal processing is highly desirable in future optical networks for its high-speed processing without optical-electrical-optical conversion. Recent progress of silicon photonics and graphene has driven the increasing research interest of ultra-compact highly efficient chip-scale all-optical signal processing. In this Letter, by exploiting a graphene-silicon microring resonator (GSMR), we propose and experimentally demonstrate channel-selective wavelength conversion of multi-channel quadrature amplitude modulation (QAM) signals. Efficient selective conversion of four-channel 16-QAM signals are observed. The selective suppression ratio and bit error rate of selective conversion are studied, showing favorable operation performance. The proposed channel-selective wavelength conversion of multi-channel signals using GSMR may find various applications in future advanced optical networks for robust data management.