Surface acoustic waves (SAW) are used in many technological applications like small RF filters in everyday electronics. Additionally, a lot of research has been done to use SAWs in quantum...Show moreSurface acoustic waves (SAW) are used in many technological applications like small RF filters in everyday electronics. Additionally, a lot of research has been done to use SAWs in quantum technologies like quantum transduction. In this thesis, Young’s double-slit experiment has been carried out using SAWs on anisotropic gallium arsenide with the goal of comparing the results to the existing scalar optical diffraction theory. Simulations have been made based on the mentioned theory and the measurements have been done using a Michelson interferometer with lock-in detection. Despite non-ideal samples, the diffraction and interference of SAWs have been observed. The experimental data agrees somewhat with the simulations taking into account the anisotropic wave speed. We have also measured the angular phase velocity relation of gallium arsenide and found it to be consistent with the literature.Show less
In this research project, we attempt to develop numerical simulation models to investigate surface acoustic waves (SAWs) and how they can be efficiently excited using interdigital transducers (IDTs...Show moreIn this research project, we attempt to develop numerical simulation models to investigate surface acoustic waves (SAWs) and how they can be efficiently excited using interdigital transducers (IDTs). These devices already find use in applications such as filtering devices for mobile communication systems. We identified the equation of motion in solids, Gauss’ law of electrostatics and the piezoelectric constitutive equations combined with material properties as the basic physics required to model IDTs. Based on these equations, we developed 2D and 3D finite element method (FEM) simulations in COMSOL, with lithium niobate and gallium arsenide as substrate materials, which we used to investigate the IDT frequency response. We also investigated the transient response of IDTs. Our results are in good agreement with analytic theory, which validates our model and approach. These models can now be used to optimize IDT device designs. Lastly, we propose and implement the first steps toward an optical setup based on a Michelson interferometer to detect surface acoustic waves.Show less
