System parameter analysis on devices with Bi-stable characteristics

In this paper an investigation has been done on the parameters of a hysteretic bi-stable device. From a design point of view it is important to know the regions where this bi-stability occurs and is fully functional with respect to its subsystem parameters. Specifically a known structure of photonic Schmitt trigger that consist of two inverting amplifiers, each characterized by -m (slope), A (y-intercept) and B (constant base) parameters is considered. In addition to a complete mathematical analysis of the system, this paper also describes how m, A and B can be properly chosen in order to satisfy certain system conditions. For a special case of B = 0, it is found and shown that we must have (m₁ <; 1 & m₂ > 1) as absolute conditions for the bi-stable device (m > 0 is assumed). Also system conditions add more restrictions to these absolute conditions as discussed in the last section of this paper.