Leaky acoustic waves in acousto-optic and acoustoelectric interaction

Acoustic wave and light – acousto-optic (AO) interaction provides an efficient tool for probing the acoustic wave properties not only at a crystal surface but also at any point within its bulk. This is topical in the design of the bulk wave devices for various applications. Meanwhile, there have been a few investigations of AO diffraction by (interdigital transducer) IDT-generated bulk waves, but not of the diffraction due to the radiation from leaky surface acoustic waves (SAWs). On the other hand, AO interaction enables efficient control of light parameters. Bulk wave AO devices have found numerous applications as light modulators, deflectors, tunable filters. In this PhD thesis, the experimental investigation and theoretical model of anisotropic light diffraction by leaky SAW radiation into crystal bulk in ZX-LiNbO3 and YX-LiTaO3 are reported. This type of interaction allows one to combine benefits of the IDT technology with the enhanced interaction efficiency of bulk-wave-type interaction. Mixed-valence perovskite manganites were studied intensively in recent years due to the observed paramagnetic to ferromagnetic transition at Curie temperature, colossal magnetoresistance effect, a variety of unique properties and potential at various applications. Due to the strong Jahn-Teller electron-phonon coupling the acoustic technique is effective tool for investigations of manganites. In this PhD thesis, the experimental investigation of the leaky SAW radiation propagating in thin film La0.67Sr0.33MnO3 – LiNbO3 and La0.67Sr0.33MnO3 – LiTaO3 structures is reported and theoretical model of acoustic wave propagating in a layered thin conductive film – piezoelectric structure is applied to describe the experimental results