Measurement of Magnetization or Magnetic Susceptibility of Small Particles and Measurement of Field Gradients of Domain Walls
Original Publication Date: 1987-Sep-01
Included in the Prior Art Database: 2005-Feb-01
An instrument is described which (a) permits the force calibration of an Ultra-Small Force Probe (USFP) to enable it to measure the magnetic susceptibility of a single small particle and (b) enables an Atomic Force Microscope (AFM) to measure small-scale inhomogeneities of the magnetic field which occur on magnetic domain walls between domains of different magnetization orientation. This instrument comprises a needle having a fine tip firmly attached to an elastic medium, a small magnetic particle attached to the tip of the needle, a means for measuring very small displacements of the needle, means for producing a known magnetic field with a field gradient, and means such as piezoelectric drivers which can move the needle and its attached magnetic particle with respect to the magnetic field in very small calibrated steps.