Measurement of surface tension for molten silicon by electromagnetic levitation combined with static magnetic field

We have attempted to superimpose a static magnetic field to electromagnetic levitation, so as to investigate the possibility, whether application of a magnetic field can improve a surface tension measurement technique using an oscillating drop method. Movement of gravitational center of a droplet, which causes measurement error, was suppressed by applying a magnetic field. Amplitude of oscillation of the "Area" and "Sum" modes were attenuated vanishingly above 0.5T, whereas oscillation of the "Diff" mode exclusively remained although the amplitude became small in the magnetic field. Using frequencies of these three modes, frequency of surface oscillation of m = 0, m = ±1 and m = ±2 modes were derived. This suggests that oscillation of the m = 0 and m = ±1 modes are damped by applying a static magnetic filed. However, there still remains an argument, whether remained oscillation really corresponds to that of m = ±2 or that of axial rotation in the static magnetic field.