50-Gb/s silicon quadrature phase-shift keying modulator
10 September 2012
We report the first successful demonstration of quadrature phaseshift keying (QPSK) modulation using two nested silicon Mach-Zehnder modulators. 50-Gb/s QPSK signal is generated with only 2.7-dB optical signal-to-noise ratio penalties from the theoretical limit at a bit-error ratio of 10-3. This result validates that silicon photonics could be a viable and powerful platform of photonic integrated circuits in coherent optical communications. ©2012 Optical Society of America OCIS codes: (250.5300) Photonic integrated circuits; (060.1660) Coherent communications; (250.7360) Waveguide modulators; (130.0250) Optoelectronics.