Polarization-insensitive wavelength conversion of 40 Gb/s NRZ-DPSK signals in a silicon polarization diversity circuit

Abstract

International audiencePolarization insensitive wavelength conversion of a 40 Gb/s non-return-to-zero (NRZ) differential phase-shift keying (DPSK) data signal is demonstrated using four-wave mixing (FWM) in a silicon nanowire circuit. Polarization independence is achieved using a diversity circuit based on polarization rotators and splitters, which is fabricated by a simple process on the silicon-on-insulator (SOI) platform. Error-free performance is achieved with only 0.5 dB of power penalty compared to the wavelength conversion of a signal with well optimized input polarization. Additionally, data transmission over 161 km standard single-mode fiber (SSMF) is demonstrated at 40 Gb/s using optical phase conjugation (OPC) in the proposed circuit

Polarization Insensitive Wavelength Conversion in a Low-Birefringence SiGe Waveguide

“…While FWM is an inherently polarization-dependent process requiring accurate control of the state of polarization of the mixing waves, implementations that achieve polarization insensitive operation have been proposed. Such schemes employing either two orthogonally polarized pumps [9] or polarization diversity [10] have already been widely demonstrated in fiber-based devices, but their adoption in silicon-based systems is still rather limited [11,12]. Polarization diversity is widely used in photonics to overcome the strong birefringence of devices.…”

Controlling free-carrier temporal effects in silicon by dispersion engineering

“…On-chip demonstrations of χ 3 processes in silicon include soliton compression [3], supercontinuum generation [4], photon pair generation [5], Raman lasing [6], and third-harmonic generation [7], as well as applications in optical communications, interconnects, and switching [9][10][11][12][13]. The advantages of silicon for nonlinear photonic devices include its large Kerr nonlinearity and its capacity for subwavelength confinement of light.…”

All-optical signal processing using silicon devices

“…Fig. 4 shows an integrated polarisationdiversity chip using two c-Si nanowires with a polarisation splitter and rotator (PSR) in either end 35 . An integrated polarisation-insensitive optical ring resonator based DPSK demodulator was implemented in a similar way 36 .…”