Photonic Integrated Circuits (PIC) have multiple relatively slow tuning degrees of freedom (DOF), that must be adjusted in order to stabilize the PICs to their optimum operating points. Methods are needed to perform this stabilization. Without such methods, large scale integration of many photonic devices on the PIC would not be possible. Methods are needed to perform stabilization of the multi-dimensional operating point of the PIC a minimum or a maximum by tuning a large number of DOFs based on observing one or a few probe point(s). we adopt the ES control methodology and apply it to PIC stabilization. This is based on dithering each of the tuning DOFs with low level AC signals superposed onto the slow controls applied to these tuning DOFs. We further enhance the prior art ES control methodology with a digital iterative frame-based Discrete-Multi-Tone (DMT) novel method, akin to OFDM transmission and detection in communication theory (the key idea is to uses mutually orthogonal multitone signals as dithers superposed onto each of the tuning DOFs).
- Simplify PIC design
- Enhance integration
- Increase performance and yield
Applications and Opportunities
- Stabilization of Photonic integrated circuits (PIC) with two or more tuning DOFs for optical logic and computing