The influence of temporal phase difference of m=±2 oscillations on surface frequency analysis for levitated droplets

The oscillations of an electromagnetically levitated molten silicon droplet were analyzed. Analysis was carried out under a superimposed static magnetic field, where the m=±2 oscillation is dominant and the droplet rotates. A phase unwrapping method was used to reveal sample rotation. The oscillation frequency of the longest diameter Dmax and difference of radii along the X and Y axes, R−, were analyzed using an image of the droplet as seen from the top of the sample. The m=+2 and m=−2 oscillations were analyzed theoretically using spherical harmonics, and it was found that a temporal phase difference between m=+2 and −2 oscillations causes apparent rotation of the samples, which causes unequal intensities of the m=±2 peaks which are split by the droplet rotation.