Magnetic Metastability of the Photo-Induced State of CI x Co[Fe(CN)6] y Prussian Blue Analogues (CI=Rb, Cs)

A generic feature of photo-induced magnetic structures is reported, on the example of the photo-magnetic Prussian Blue analogues C _x Co[Fe(CN)₆] _y , zH₂O (C=Rb, Cs): the magnetic metastability of the “raw photo induced” (RPI) state obtained at low temperatures (below T _C) and in low magnetic fields (below H _C). The RPI state is characterised by a non-relaxed domain structure, due to the lack of thermal fluctuations during the building process of the ferrimagnetic domains. It evolves irreversibly under the effect of temperature or magnetic field. Some insight is given into the building mechanism of the RPI state, by consideration of the progressive increase of the Curie temperature. This revised version was published online in July 2006 with corrections to the Cover Date.