Integrated wavelength selector
Integrated wavelength selectors are described. The wavelength selector may include silicon nitride ring resonator disposed vertically between a heater and a temperature sensor. The temperature sensor may be formed of silicon in some embodiments. The wavelength selector may be coupled to the output port of a tunable laser, or may be disposed within a laser cavity.
1. An integrated wavelength selector, comprising:
a substrate;
an integrated heater on the substrate;
an integrated temperature sensor on the substrate; and
a ring waveguide comprising a first material disposed vertically between the integrated heater and the integrated temperature sensor.
2. The integrated wavelength selector of claim 1 , wherein the integrated temperature sensor comprises a second material.
3. The integrated wavelength selector of claim 2 , wherein the second material comprises one or more types of doped silicon.
4. The integrated wavelength selector of claim 2 , wherein the integrated temperature sensor is a resistive temperature sensor.
5. The integrated wavelength selector of claim 2 , wherein the second material is a resistive material.
6. The integrated wavelength selector of claim 1 , wherein the first material and the second material are different.
7. The integrated wavelength selector of claim 1 , wherein the first material exhibits a lower temperature coefficient of resonant frequency (TCF) than silicon.
8. The integrated wavelength selector of claim 1 , wherein the integrated heater is a ring substantially overlying the ring waveguide.
9. The integrated wavelength selector of claim 1 , wherein the integrated wavelength selector is disposed in a cavity of a tunable laser.
10. The integrated wavelength selector of claim 1 , further comprising a plurality of temperature isolation trenches disposed inside and outside the integrated temperature sensor.