56Gbaud DP-QPSK receiver module with a monolithic integrated PBS and 90° hybrid InP chip

A 56Gbaud dual polarization quadrature phase shift keying (DP-QPSK) receiver module is presented including an InP receiver chip. The chip consists of monolithically integrated polarization beam splitters (PBS), 90° hybrids and balanced photodiodes.

I. Introduction

The 100G Ethernet standard has found its way into commercial applications. For this reason, researches are focusing on data rates per wavelength channel beyond 100Gb/s in order to increase the date capacity of the next generation Ethernet standard. Advanced modulation formats such as dual polarization quadrature phase shift keying (DP-QPSK) are approved to increase the spectral efficiency [1].