Electro-optic waveguide with polarization control

An optoelectronic device, comprising:

• a substrate;
• an optical waveguide disposed on the substrate, the waveguide comprising a uniaxial electro-optical crystal having a principal axis parallel to a propagation axis of the waveguide;
• and
• electrodes configured to apply an electric field to the electro-optical crystal so as to rotate a polarization of an optical wave as the optical wave propagates through the waveguide,
• wherein the electrodes comprise at least first electrodes configured to apply a first electric field along a first axis transverse to the propagation axis and second electrodes configured to apply a second electric field along a second axis transverse to the propagation axis and to the first axis, and
• wherein the electrodes further comprise third electrodes configured to apply a third electric field along the propagation axis so as to zero an electrical bias across the electro-optical crystal along the propagation axis.

An optoelectronic device, comprising:

• a substrate;
• an optical waveguide disposed on the substrate, the waveguide comprising a uniaxial electro-optical crystal having a principal axis parallel to a propagation axis of the waveguide;
• and
• electrodes configured to apply an electric field to the electro-optical crystal so as to rotate a polarization of an optical wave as the optical wave propagates through the waveguide,
• wherein the electrodes are configured to apply the electric field to the electro-optical crystal so as to rotate a first polarization of a first guided mode propagating in the waveguide into alignment with a second polarization of a second guided mode propagating in the waveguide.

A method for optical control, comprising:

• forming an optical waveguide on a substrate, the waveguide comprising a uniaxial electro-optical crystal having a principal axis parallel to a propagation axis of the waveguide;
• and
• applying an electric field to the electro-optical crystal so as to rotate a polarization of an optical wave as the optical wave propagates through the waveguide,
• wherein applying the electric field comprises applying a first electric field along a first axis transverse to the propagation axis and applying a second electric field along a second axis transverse to the propagation axis and to the first axis and adjusting voltages that are applied to the electro-optical crystal so as to cause the polarization of the optical wave to rotate by a selected rotation angle over a length of the electro-optical crystal.

A method for optical control, comprising:

• forming an optical waveguide on a substrate, the waveguide comprising a uniaxial electro-optical crystal having a principal axis parallel to a propagation axis of the waveguide;
• and
• applying an electric field to the electro-optical crystal so as to rotate a polarization of an optical wave as the optical wave propagates through the waveguide,
• wherein applying the electric field comprises rotating a first polarization of a first guided mode propagating in the waveguide into alignment with a second polarization of a second guided mode propagating in the waveguide.