Optical modulator and method of use

An optoelectronic device for modulation, comprising:

• an input waveguide;
• a first intermediate waveguide and a second intermediate waveguide, each coupled to the input waveguide via an input coupler;
• an output waveguide, coupled, via an output coupler, to the first intermediate waveguide and to the second intermediate waveguide;
• a first heater on the first intermediate waveguide;
• and
• a second heater on the second intermediate waveguide,
• wherein:
• the first intermediate waveguide includes a first modulating component connected in series with a first phase shifting component;
• and
• the second intermediate waveguide includes a second modulating component connected in series with a second phase shifting component,
• wherein:
• the input coupler is a variable input coupler;
• or
• the output coupler is a variable output coupler,
• wherein the input coupler comprises a first Mach-Zehnder interferometer,
• wherein the first Mach-Zehnder interferometer comprises a multimode interference (MMI) coupler, and
• wherein the optoelectronic device comprises a second Mach-Zehnder interferometer, the second Mach-Zehnder interferometer including:
• as a variable input coupler of the second Mach-Zehnder interferometer, the first Mach-Zehnder interferometer;
• as a first arm of the second Mach-Zehnder interferometer, the first intermediate waveguide;
• as a second arm of the second Mach-Zehnder interferometer, the second intermediate waveguide;
• and
• as a variable output coupler of the second Mach-Zehnder interferometer, a third Mach-Zehnder interferometer.

A system, comprising an optoelectronic device for modulation and a control circuit, wherein the optoelectronic device comprises:

• an input waveguide;
• a first intermediate waveguide and a second intermediate waveguide, each coupled to the input waveguide via an input coupler;
• and
• an output waveguide, coupled, via an output coupler, to the first intermediate waveguide and to the second intermediate waveguide,
• wherein:
• the first intermediate waveguide includes a first modulating component connected in series with a first phase shifting component;
• and
• the second intermediate waveguide includes a second modulating component connected in series with a second phase shifting component,
• wherein:
• the input coupler is a variable input coupler;
• or
• the output coupler is a variable output coupler,
• wherein the input coupler comprises a first Mach-Zehnder interferometer,
• wherein the first Mach-Zehnder interferometer comprises a multimode interference (MMI) coupler,
• wherein the optoelectronic device comprises a second Mach-Zehnder interferometer, the second Mach-Zehnder interferometer including:
• as a variable input coupler of the second Mach-Zehnder interferometer, the first Mach-Zehnder interferometer;
• as a first arm of the second Mach-Zehnder interferometer, the first intermediate waveguide;
• as a second arm of the second Mach-Zehnder interferometer, the second intermediate waveguide;
• and
• as a variable output coupler of the second Mach-Zehnder interferometer, a third Mach-Zehnder interferometer, and
• wherein the control circuit is configured to control a plurality of heaters, to:
• maintain a relative phase in the first arm and in the second arm, at a first operating point,
• maintain a wavelength of maximum normalized extinction ratio for the first modulating component at a second operating point, and
• maintain a wavelength of maximum normalized extinction ratio for the second modulating component at a third operating point.