Manganese-doped yttrium orthoaluminate: A potential material for holographic recording and data storage

Abstract

Optical properties of manganese-doped yttrium orthoaluminate crystals (Mn:YAlO 3 ), grown by the Czochralski technique, are reported. Luminescence and absorption spectra indicate the presence of Mn 4ϩ ions in as-grown crystals, and Mn 3ϩ , Mn 4ϩ , and Mn 5ϩ ions simultaneously in photoexcited crystals. A permanent diffraction grating, erasable by heating, was obtained in the crystals with diffraction efficiency of more than 50% at 514.5 nm reading wavelength and 1-2 % in 632-930 nm wavelength range. Reading at wavelengths longer than 630 nm did not damage the recorded grating. The electro-optical effect observed in the photoexcited crystals implies that manganese ions disturb the YAlO 3 crystal structure so that it becomes noncentrosymmetric.

Irreversible effects in LaGa1−xMnxO3

“…In both cases the irreversible effects are apparently related to the ionization of Mn ions and redistribution of charge. In both cases, the memory effects last for a long time at room temperature and demonstrate very slow logarithmic relaxation in a similar time scale (half-lifetime is ~ 122 years in Mn:YalO 3 [8], and ~300 years in LaGaMnO 3 ). In similarity, both effects are completely erasable by heating the crystals to a temperature of 230-300 C, which is higher than the phase transformation temperature.…”

“…On the other hand, high-resistivity perovskite materials with very low concentration of Mn ions also exhibit interesting memory effects. Mn doped yttrium orthoaluminates, Mn:YAlO 3 , high-quality optical single crystals, demonstrate significant changes in color and photorefractive index induced by photo illumination [8,9]. These effects are quasipermanent, lasting for many years at room temperature, and completely erasable by heating the crystal up to ~ 230 C. To better understand the origin of the irreversibility in perovskites with different content of Mn ions, we have studied the series of LaGa 1-x Mn x O 3 with concentration of Mn ions varying from 2% to 100%.…”

Growth and spectroscopic properties of RE, Mn:YAP (RE=Yb and Ce) photorefractive crystals

“…There is close to linear dependence of the maximum achievable Mn 5+ photoinduced absorption and Mn 4+ absorption (480 nm) in nonexposed crystal [2]. At room temperature (RT), long dark storage time of more than 120 years has been anticipated in Mn:YAP crystal [4], and the holographic grating can be easily erased at the temperature of 270 1C or above [1][2][3][4]. Such characteristics in combination with the high quality and low optical scattering of the crystal make Mn:YAP the most promising material for holographic recording and data storage.…”

“…Yttrium orthoaluminate crystal doped with manganese (Mn:YAP) has been reported as a promising material in holographic recording and data storage [1]. A high diffraction efficiency of more than 50% has been demonstrated [1,2].…”

“…YAP has a distorted perovskite structure that belongs to the orthorhombic centrosymmetric space group P nma [1] respectively. The powders were totally mixed and pressed into the form of blocks which were sintered at 1200 1C for 10 h in air.…”