Active photonic devices incorporating high dielectric constant materials
An optical switch structure includes a substrate, a first electrical contact, and a first material having a first conductivity type electrically connected to the first electrical contact. The optical switch structure also includes a second material having a second conductivity type coupled to the first material, a second electrical contact electrically connected to the second material, and a waveguide structure disposed between the first electrical contact and the second electrical contact. The waveguide structure includes a waveguide core coupled to the substrate and including a first material characterized by a first index of refraction and a first electro-optic coefficient and a waveguide cladding at least partially surrounding the waveguide core and including a second material characterized by a second index of refraction less than the first index of refraction and a second electro-optic coefficient greater than the first electro-optic coefficient.
1. An optical device comprising:
a substrate;
a first electrical contact;
a second electrical contact; and
a waveguide structure disposed between the first electrical contact and the second electrical contact and comprising:
a waveguide core coupled to the substrate and including a first material characterized by a first index of refraction and a first electro-optic coefficient; and
a waveguide cladding at least partially surrounding the waveguide core and including a second material characterized by a second index of refraction less than the first index of refraction and a second electro-optic coefficient greater than the first electro-optic coefficient.
2. The optical device of claim 1 wherein the first electro-optic coefficient and the second electro-optic coefficient are the Kerr coefficient χ (3) .
3. The optical device of claim 1 wherein the first electro-optic coefficient and the second electro-optic coefficient are the Pockels coefficient χ (2) .
4. The optical device of claim 1 wherein the waveguide core supports a guided mode characterized by an optical power, wherein a majority of the optical power is contained in the waveguide core.
5. The optical device of claim 1 wherein the waveguide core comprises silicon.
6. The optical device of claim 5 wherein the waveguide core comprises silicon nitride.
7. The optical device of claim 1 wherein the first electro-optic coefficient equals approximately zero.
8. The optical device of claim 1 wherein the waveguide core supports a TE polarization mode.
9. The optical device of claim 1 wherein:
the first electrical contact and the second electrical contact are configured to generate an applied electric field produced in the waveguide structure that is characterized by a direction; and
the waveguide cladding is characterized by an electro-optic coefficient tensor having a maximum value aligned along the direction.
10. The optical device of claim 9 wherein a guided mode supported by the waveguide core has a direction of polarization aligned with the direction.
11. The optical device of claim 9 wherein the waveguide cladding is characterized by a DC Kerr effect and a Pockels effect having a same sign.
12. The optical device of claim 11 wherein the DC Kerr effect is positive and the Pockels effect is positive.
13. The optical device of claim 12 wherein the waveguide cladding comprises a first material type, a majority of polarization domains are aligned with a positive z-direction, and a direction of the applied electric field is negative.
14. The optical device of claim 12 wherein the waveguide cladding comprises a first material type, a majority of polarization domains are aligned with a negative z-direction, and a direction of the applied electric field is positive.
15. The optical device of claim 12 wherein the waveguide cladding comprises a second material type, a majority of polarization domains are aligned with a positive z-direction, and a direction of the applied electric field is positive.
16. The optical device of claim 12 wherein the waveguide cladding comprises a second material type, a majority of polarization domains are aligned with a negative z-direction, and a direction of the applied electric field is negative.