title: Optical filtering enabled by cascaded parametric amplification.
abstract: A cascaded parametric amplifier consists of a first parametric amplifier, which amplifies an input signal and generates an idler, which is a copy of the signal, a signal processor, which controls the phases of the signal and idler, and a second parametric amplifier, which combines the signal and idler in a phase-sensitive manner. In this paper, cascaded parametric amplification is modeled and the conditions required to maximize the constructive-destructive extinction ratio are determined. The results show that a cascaded parametric amplifier can be operated as a filter: A desired signal-idler pair is amplified, whereas undesired signal-idler pairs are deamplified. For the desired signal and idler, the noise figures of the filtering process (input signal-to-noise ratio divided by the output ratios) are only slightly higher than those of the copying process: Signal-processing functionality can be achieved with only a minor degradation in signal quality.
authors.forename: C J
authors.initials: CJ
authors.lastname: McKinstrie
authors.forename: J M
authors.initials: JM
authors.lastname: Dailey
authors.forename: A
authors.initials: A
authors.lastname: Agarwal
authors.forename: P
authors.initials: P
authors.lastname: Toliver