ISSN:
1434-6036
Keywords:
PACS. 75.50.Xx Molecular magnets - 78.40.Ha Other nonmetallic inorganics - 82.20.Mj Nonequilibrium kinetics
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
Abstract: We studied the photo-excitation process, the relaxation of the photo-excited state towards the stable state, and the photo-induced magnetic properties of the Prussian blue analogue Rb0.52Co [Fe(CN)6]0.84, 2.3 H2O. Magnetic, Mössbauer and reflectivity measurements have been performed during and after illumination. The efficiency of the photo-excitation device is maximum at nm. The process, however, is severely hindered by bulk absorption of the light; it is rapidly completed at the surface of the sample and then proceeds slowly in the bulk. Under the effect of photo-excitation the system turns from a dia- to a ferri- magnet, with a value K, indicative of the transformation of the material due to the following optical electron transfer: Thermal relaxation towards the stable electronic state is observed in the 95-110 K temperature interval, obeying a self-accelerated kinetics. At low temperature, a weak, non-exponential, relaxation is detected. These features are discussed in terms of co-operative effects in the frontal process of photo- excitation. The peculiarities of a photo-excited state created below the magnetic ordering temperature are discussed. A metastable magnetic state has been observed in low fields, denoted “Raw Photo-Induced State" (RPI), with a magnetization curve in-between the field-cooled and zero-field-cooled curves.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s100510050112
