By using the Generalized Lorentz-Mie Theory (GLMT), which was successfully adapted from optics to acoustics, we present a thorough parametric study of acoustic forces in a standing-wave levitation trap, which allows us to identify the most relevant parameters of the levitation devices, while exploring the size ranges of the objects that can be acoustically levitated in these kinds of traps. We show that particles can be trapped either in pressure nodes or antinodes, depending solely on their size. This is analogous to the particle size-effect found in optical traps with complex light potentials. We present theoretical and experimental results for airborne levitation that are in excellent agreement.
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