bistable system

bistable system

[¦bī¦stā·bəl ′sis·təm]
(chemistry)
A chemical system with two relatively stable states which permits an oscillation between domination by one of these states to domination by the other.
References in periodicals archive ?
Noise-Induced Dynamics in Bistable System with Delay.
Such a bistable system can operate as a detector when a sufficiently strong external force -- a signal -- nudges the ball over the barrier into the second well (analogous to switching the direction in which light travels in a ring laser).
This is why real samples do not exhibit linear responses or infinite susceptibility; instead, they behave as bistable systems that switch between different states of internal alignment at critical values of the external field (see Appendix).