Magnetic Ejection and Oscillation of Diamagnetic Crystals Observed in Microgravity

Translations induced by a field gradient force are newly reported on various diamagnetic crystals that are released in microgravity (mu G) produced by a drop capsule. A crystal released near a field center (B similar to 1 T) with negligible initial velocity translates through a diffused gas medium, in a direction of monotonically decreasing field. In a given field distribution, the velocity of the crystal uniquely depends on the intrinsic diamagnetic susceptibility chi(DIA) of the material; velocity is independent of the mass m of particles. The general features of rotational oscillation caused by field-induced anisotropy energy are studied on the basis of previous experimental data; the rotational oscillation of a magnetically stable axis with respect to the direction of homogeneous field has recently been observed for various diamagnetic crystals in mu G. At a given. field intensity, the period of oscillation is uniquely determined by the intrinsic diamagnetic anisotropy Delta chi(DIA) and Im(-1) of crystals; I denotes the moment of inertia of crystals. The period is independent of m. In a long duration of mu G, field-induced translation and rotation are generally observable for diamagnetic solids at low field intensities. By observing the two motions in mu G, chi(DIA) and Delta chi(DIA) are obtained without introducing a sample holder, and without performing m measurement; magnetization becomes detectable for a single particle with a limitlessly small size, under the condition that field-induced motions of particles are observed.