Electro-optic coefficients r13 and r33 of singly Er3+-doped and In3+/Er3+-codoped LiNbO3 crystals

Electro-optic properties of singly and doubly doped lithium niobate crystal by rare earth elements for optoelectronic and laser applications

“…Based on the general model of the role of the dopant for the EO coefficients of inorganic crystals and thus for LN, it is now well established that the ionic contribution is the predominant contribution considering the change in the composition, i.e. the Li/Nb ratio of in the doping effect [22,23,[50][51][52][53]56,57]. In this model, the two main contributions being considered are the deformability of the oxygen NbO 6 and LiO 6 octahedron, at low dopant concentration and the change in the ionic and electronic polarizabilities of the Nb ions for higher concentrations.…”

“…It is thus challenging to know the EO properties of singly or doubly doped LN with rare-earth elements as Er 3+ , Yb 3+ and Ho 3+ and to determine if the co-doping affects the EO properties of singly doped LN. As above mentioned, Du et al [56,57] characterized the EO properties of singly Er 3+ doped and In 3+ -Er 3+ co-doped LN crystals. Their experimental results show that Er 3+ doping affects the EO coefficient r 13 (beam propagation along the axis x (or y) of the crystal with an electric field applied along z) when the dopant concentration is close the concentration threshold, whereas, In 3+ -Er 3+ co-doping does not cause the change of the EO coefficients r 13 and r 33 , which represents an interesting advantage for applications based on EO modulation.…”

“…On contrary of the numerous functional properties for divalent and tetravalent-doped LN crystals available in literature as mentioned above, only few studies mentioned the doping of LN with trivalent ions such as Sc 3+ and In 3+ [39,41,45,54,55]. Except the contributions of Du et al [56,57] on LN crystals doped with Er 3+ ions, no work has been devoted to the study of the dielectric and electrooptical properties of crystals doped or co-doped with others rare-earth elements as Er 3+ , Yb 3+ and Ho 3+ as function of the concentration and of the structural properties. In a previous work [41], by EO and dielectric measurements it was shown that In 3+ doped congruent LN crystals present a smaller optical damage, for a concentration threshold equal to 1.7 mol%, i.e.…”

Composition dependence of the electro‐optic properties of iron‐doped lithium niobate crystals mounted as bulk modulator

“…Numerous studies point that LN crystals present a large set of possibilities to control, that is, suppress or enhance the photorefractive effect for adaptation to opto‐electronic devices and applications. With a significant but nonexhaustive list of dopants, currently the most used dopants for functionalizing LN crystals via the electro‐optic effect, include divalent Mg 2+ , and Zn 2+ , trivalent In 3+ , Er 3+ , and Sc 3+ , and tetravalent Zr 4+ , Sc 4+ , and Hf 4+ ,. Moreover, in the fields of optical information processing, holographic volume storage, phase conjugation or interferometric holography, iron‐doped LN crystals present the fascinating possibilities, thanks to their high photorefractive sensitivity.…”

“…The qualification of the electro‐optic properties of pure or doped LN crystal mobilizes many teams since many years and until now in connection with the improvement of the qualities of the obtained crystals, thanks to advances in growth techniques allowing new and more efficient applications. The electro‐optic (EO) effect was studied in pure LN crystal and in LN crystals doped or co‐doped with various dopants as one can see in the following set of references . A special mention can be made for the EO studies relative to iron‐doped LN crystals as iron exists in LN structure under two‐valence state, Fe 2+ and Fe 3+ , depending on the composition, the growth process, and the postgrowth treatments (reduction or oxidation annealing).…”