A Direct Coupling Coherent Quantum Observer for an Oscillatory Quantum Plant

A direct coupling coherent observer is constructed for a linear quantum plant which has oscillatory solutions. It is shown that a finite time moving average of the quantum observer output can provide an estimate of the quantum plant output without disturbing this plant signal. By choosing a sufficiently small averaging time and a sufficiently large observer gain, the observer tracking error can be made arbitrarily small.This work was supported by the Air Force Office of Scientific Research (AFOSR), under agreement number FA2386-16-1-4065. Some of the research presented in this paper was also supported by the Australian Research Council under grant FL110100020