An optical polarization-bistable element based on the Faraday effect

An optical polarization-bistable element scheme based on an He-Ne laser (λ = 3.39 μm) with a Faraday cell in the cavity is considered for the first time. A sample of such cavity having the shape of a parallelepiped has been manufactured from an yttrium iron garnet single crystal and a theoretical analysis of this element in terms of the Jones matrices has been performed. It is established that the polarization bistability can be observed for a single-trip Faraday rotation of 45°. Experiments with the device based on a hybrid bistability scheme showed that, under certain conditions, the circular polarization is reversibly switched between σ+ and σ−.