A Method for Measuring Magnetization Dynamics at the Nanoscale

Abstract

The invention relates to the field of material surface magnetic measurement, in particular to a measurement method of nano-scale magnetization dynamics. A measurement device comprises a pulse laser, adelayer, a quarter wave plate, a concave lens, a convex lens I, a plane mirror, a polarizer, a beam splitter, a convex lens II, a lens table, an atomic force microscope I, a probe I, a lens holder, an objective lens, a sample, a waveguide, a sample table, a signal generator, an oscilloscope, a detector, a bias tee, an amplifier I, a mixer, an amplifier II, an analog-to-digital converter, a computer, an atomic force microscope II, a probe II and a phase-sensitive detector. A single nanostructure can be measured, measurement of magnetization dynamics on the sample surface can reach sub-micron spatial resolution, two different atomic force microscope tips are adopted for contact mode atomic force microscope scanning and near-field time-resolved magneto-optical Kerr effect experiment respectively, GHz-band magnetization dynamics on the sample surface are detected with a frequency domain method, and higher sensitivity is realized.

Description

technical field [0001] The invention relates to the field of material surface magnetic measurement, in particular to a nanoscale magnetization dynamic measurement method capable of measuring the high-frequency dynamic magnetization of a single nanostructure on the material surface. Background technique [0002] The magneto-optical Kerr effect measurement device is an important means in the study of material surface magnetism. Its working principle is based on the magneto-optic Kerr effect caused by the interaction between light and magnetized media. Magnetic detection, and non-contact measurement can be realized, and it has important applications in the research of magnetic order, magnetic anisotropy, interlayer coupling and phase transition behavior of magnetic ultrathin films. The magneto-optical Kerr effect measurement device mainly detects the magnetization observation of the sample surface by detecting the change of the polarization state of a beam of linearly polarized...

AI Technical Summary

Problems solved by technology

The magneto-optical Kerr effect measurement device mainly detects the magnetization observation of the sample surface by detecting the change of the polarization state of a beam of linearly polarized light after it is reflected on the surface of the material. Therefore, the imaging effect is easily limited by the optical elements. Technical defect 1: The spatial resolution of the traditional focusing Kerr microscope using microscope objective lens is determined by the optical diffraction limit, so it is impossible to obtain the dynamic characteristics of magnetization at the nanometer scale; the existing technical defect 2: it is impossible to obtain higher frequency magnetization in the sample. Magnetization dynamic information, the measurement method of the nanoscale magnetization dynamics can solve the problem

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