Abstract: A system is provided for use with an optical input signal for detecting a phase difference between a first RF signal having a first phase and a second RF signal having a second phase. The system includes and optical waveguide, a first optical resonant cavity, a first RF receiver, a second optical resonant cavity and a second RF receiver. The optical resonant cavities include a non-linear electro-optical material. The first RF receiver affects the first non-linear electro-optical material of the first optical resonant cavity. The second RF receiver affects the second non-linear electro-optical material of first optical resonant cavity. The optical waveguide outputs an optical output signal based on the optical input signal as modified by the first optical resonant cavity as affected by the first RF receiver receiving the first RF signal and as modified by the second optical resonant cavity as affected by the second RF receiver.

Abstract: A system is provided for use with an optical input signal for detecting a phase difference between a first RF signal having a first phase and a second RF signal having a second phase. The system includes and optical waveguide, a first optical resonant cavity, a first RF receiver, a second optical resonant cavity and a second RF receiver. The optical resonant cavities include a non-linear electro-optical material. The first RF receiver affects the first non-linear electro-optical material of the first optical resonant cavity. The second RF receiver affects the second non-linear electro-optical material of first optical resonant cavity. The optical waveguide outputs an optical output signal based on the optical input signal as modified by the first optical resonant cavity as affected by the first RF receiver receiving the first RF signal and as modified by the second optical resonant cavity as affected by the second RF receiver.

Abstract: A robust fabrication process for selective area growth of semiconductors in growth windows is provided. Sidewall growth is eliminated by the presence of a spacer layer which covers the sidewalls. Undesirable exposure of the top corners of the growth windows is prevented by undercutting the growth window prior to deposition of the dielectric spacer layer. The effectiveness of this process has been demonstrated by selective-area growth of Ge and Ge/SiGe quantum wells on a silicon substrate. Integration of active optoelectronic devices with waveguide layers via end-coupling through the dielectric spacer layer can be reliably accomplished in this manner.