Patent ID: 11953766
Assignee: HEWLETT PACKARD ENTERPRISE DEVELOPMENT LP
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 14:
15. A method for tuning a directional coupler, the method comprising:
applying a first voltage bias to a first metal oxide semiconductor (MOS) capacitor, the first MOS capacitor formed in a first optical waveguide;
modulating a first refractive index of the first optical waveguide by adjusting the first voltage bias, wherein the first refractive index changes based on carrier concentration in the first MOS capacitor responsive to the first voltage bias;
applying a second voltage bias to a first mesa disposed on the first MOS capacitor, the first mesa comprising a first optically active region;
modulating optical gain or optical loss introduced by the first mesa into the first optical waveguide by adjusting the second voltage bias, wherein the optical gain or the optical lose changes based on carrier concentration in the first optically active region responsive to the second voltage bias; and
tuning a gain to loss ratio and refractive index difference between the first optical waveguide and a second optical waveguide based on modulating the first refractive index and the optical gain or optical loss.