Low voltage traveling wave electro-absorption modulator for high bandwidth operation

An electro-absorption modulator (EAM) device comprising:

• an optical waveguide comprising a continuous multi-quantum well (MQW) layer with alternating active sections and passive sections, wherein, in an unbiased state, portions of the continuous MQW layer disposed in respective longitudinal portions of each of the active sections have an energy gap defining an active energy gap value, portions of the continuous MQW layer disposed in respective longitudinal portions of each of the passive sections have an energy gap defining a passive energy gap value, and each active energy gap value is less than each passive energy gap value;
• a segmented traveling wave electrode structure comprising a plurality of electrode segments, wherein each electrode segment is disposed on a corresponding active section;
• and
• an electrical transmission line operatively coupled to the electrode segments, wherein the electrical transmission line is configured to facilitate a propagation of an electrical signal therethrough, and wherein the electrical transmission line is configured to be directly electrically coupled to an unamplified radio frequency (RF) source to provide direct drive modulation to the EAM device.

A method comprising:

• receiving, from a laser source, a continuous wave (CW) light via an optical waveguide of an EAM device, wherein the optical waveguide comprises a segmented traveling wave (S-TW) electrode structure comprising a plurality of electrode segments disposed thereon, wherein the optical waveguide comprises a continuous multi-quantum well (MQW) layer with alternating active sections and passive sections, wherein, in an unbiased state, portions of the continuous MQW layer disposed in respective longitudinal portions of each of the active sections have an energy gap defining an active energy gap value, portions of the continuous MQW layer disposed in respective longitudinal portions of each of the passive sections have an energy gap defining a passive energy gap value, and each active energy gap value is less than each passive energy gap value;
• receiving, from an unamplified radio frequency (RF) source, an electrical signal via an electrical transmission line operatively coupled to the electrode segments, wherein the unamplified RF source is directly electrically coupled to the electrical transmission line to provide direct drive modulation to the EAM device;
• and
• generating, using the EAM device, an optical output signal based on at least the CW light.