Attempt to Detect Magnetization of a Single Magnetic Grain by Observing Its Field-Induced Translation in μG Condition

Abstract

Magnetization of a single grain is detected with an accuracy of about 10% by observing its translation through an area of microgravity; here translation was caused by an attractive field-gradient force produced by a static magnetic field. The above measurements were performed on paramagnetic pyroxene (MgFe)SiO₃ grains as well as two different types of ferrite grains. It was experimentally confirmed that the obtained value of magnetization was independent to the value of sample mass, which indicated that translation of a grain was uniquely controlled by a field-induced potential. Magnetization of a single magnetic grain is measurable irrespective of its size, because mass measurement of sample is unnecessary in the proposed method. The measurement is not interrupted by a signal emitted from sample holder. The present method to measure magnetization is applicable in identifying the material of a small magnetic grain in a nondestructive manner.