MZM LINEAR DRIVER FOR SILICON PHOTONICS DEVICE CHARACTERIZED AS TWO-CHANNEL WAVELENGTH COMBINER AND LOCKER

摘要

The present invention includes a Mach-Zehnder modulator (MZM) linear driver configured in a differential form with two waveguides carrying two traveling waves which supports a two-channel spectral combiner integrated with a wavelength locker. By coupling a DC current source supplied with a modulation voltage with each segment thereof for providing electrical modulation signal overlapping with each of the two traveling waves. The modulated traveling waves in the two waveguides then are combined in one output signal by a multimode interference coupler. Two optical signals at ITU grid channels are separately modulated by two MZMs and combined into a silicon waveguide-based delayed-line interferometer built on a SOI substrate to produce an output signal having a free spectral range equal to twice of the spacing of the two ITU grid channels. Two dither signals can be added respectively to the two optical signals for identifying and locking corresponding two channel wavelengths.

主权项

1. A MZM linear driver applicable for wavelength combiner and locker through silicon photonics, the MZM linear driver comprising:
a first MZM material having a first length connecting a first electrode to a second electrode to transmit a first optical wave split from an input optical signal by a 1×2 MMI coupler; a second MZM material having the first length connecting a third electrode to a fourth electrode to transmit a second optical wave split from the input optical signal by the 1×2 MMI coupler; a DC coupled current source configured to couple between the first electrode and the third electrode to supply a modulation current flowing through respectively the first length and the second length driven by a modulation voltage coupled in-parallel the second electrode and the fourth electrode; a middle electrode having a second length disposed in parallel to the first MZM material and the second MZM material and subjecting to a bias voltage effectively on a first p-n junction across the middle electrode and the first MZM material of the first length and a second p-n junction across the middle electrode and the second MZM material of the first length, the second length being greater than or equal to the first length.