Optical bandpass filter from a curved segment of a detuned two-core fiber

Abstract

We present the use of a dual-core fiber as a bandpass filter. Our device is based on the fact that intrinsic detuning between the propagation constants of the two cores can be compensated for in a controlled manner by use of a loop. This compensation is made to occur for a specific frequency band, so that the resulting device acts as a bandpass filter.