Distributed CMOS driver with enhanced drive voltage for silicon optical push-pull Mach-Zehnder modulators

1. A silicon optical modulator driver comprising:

driver circuitry configured to:

electrically drive a first plurality of diodes with a first modulating signal, the first plurality of diodes disposed at differing locations on a first common optical waveguide arm of a Mach-Zehnder optical modulator; and

electrically drive a second plurality of diodes with a second modulating signal, the second plurality of diodes disposed at differing locations on a second common optical waveguide arm of the Mach-Zehnder optical modulator;

wherein at least a first diode of the first plurality of diodes is electrically connected in parallel to at least a second diode of the second plurality of diodes.

2. The silicon optical modulator driver of claim 1 , wherein the first modulating signal is an I signal.

3. The silicon optical modulator driver of claim 1 , wherein the second modulating signal is a Q signal.

4. The silicon optical modulator driver of claim 1 , wherein the driver circuitry is further configured to electrically bias at least the first diode of the first plurality of diodes using a capacitor connected in series to the first diode of the first plurality of diodes.

5. The silicon optical modulator driver of claim 1 , wherein the first diode of the first plurality of diodes has an anode electrically coupled to a cathode of the second diode of the second plurality of diodes.

6. A method comprising:

electrically driving a first waveguide arm of a Mach-Zehnder optical modulator and a second waveguide arm of the Mach-Zehnder optical modulator by providing a first modulating voltage to a first plurality of diodes disposed at differing locations on the first waveguide arm and a second modulating voltage to a second plurality of diodes disposed at differing locations on the second waveguide arm;

wherein at least a first diode of the first plurality of diodes is electrically connected in parallel to at least a second diode of the second plurality of diodes.

7. The method of claim 6 , further comprising electrically biasing at least the first diode of the first plurality of diodes using a capacitor connected in series to the first diode of the first plurality of diodes.

8. The method of claim 6 , wherein electrically driving the first waveguide arm of the Mach-Zehnder optical modulator comprises matching an optical group velocity of an optical mode propagating along the first waveguide arm with the first modulating voltage.

9. The method of claim 6 , wherein the first modulating signal is an I signal.

10. The method of claim 6 , wherein the second modulating signal is a Q signal.

11. A Mach-Zehnder optical modulator comprising:

a first waveguide arm of the Mach-Zehnder optical modulator optically coupled to an input waveguide and to an output waveguide;

a second waveguide arm of the Mach-Zehnder optical modulator optically coupled to the input waveguide and to the output waveguide;

a first plurality of diodes disposed at differing locations on the first waveguide arm;

a second plurality of diodes disposed at differing locations on the second waveguide arm; and

a driver coupled to the first plurality of diodes and coupled to the second plurality of diodes, wherein at least a first diode of the first plurality of diodes is electrically connected in parallel to at least a second diode of the second plurality of diodes.

12. The Mach-Zehnder optical modulator of claim 11 , further comprising control circuitry configured to electrically drive the first plurality of diodes and the second plurality of diodes.

13. The Mach-Zehnder optical modulator of claim 11 , further comprising a plurality of capacitors, wherein at least one capacitor of the plurality of capacitors is disposed in series to a corresponding diode of the first plurality of diodes.

14. The Mach-Zehnder optical modulator of claim 13 , wherein each capacitor of the plurality of capacitors is disposed in series to a respective diode of the first plurality of diodes.

15. The Mach-Zehnder optical modulator of claim 11 , wherein the first and the second waveguide arms are made of silicon.

16. The Mach-Zehnder optical modulator of claim 11 , wherein the first diode of the first plurality of diodes has a cathode electrically coupled to an anode of the second diode of the second plurality of diodes.

17. The Mach-Zehnder optical modulator of claim 11 , wherein the first diode of the first plurality of diodes has an anode electrically coupled to a cathode of the second diode of the second plurality of diodes.

18. The Mach-Zehnder optical modulator of claim 11 , wherein the first modulating signal is an I signal.

19. The Mach-Zehnder optical modulator of claim 11 , wherein the second modulating signal is a Q signal.