Alternating current magnetic susceptibility measuring device and measuring method thereof

Abstract

The invention provides an alternating current magnetic susceptibility measuring device. The device comprises an excitation coil which is used for generating an excitation magnetic field in an energized state, and a Hall sensor located inside the excitation coil. The Hall sensor comprises two current inputs ends and two voltage output ends. The direction of bias current in two current inputs ends is parallel to the direction of the excitation magnetic field inside the excitation coil. The device further comprises a first signal generator which is used for providing alternating current excitation of first frequency for the excitation coil and a second signal generator. The output end of the second signal generator is connected with two current inputs ends of the Hall sensor. The second signal generator is used for providing alternating current excitation of second frequency for the Hall sensor. The device further comprises a lock-in amplifier which measures the voltage output signal of the Hall sensor, and a third signal generator which provides a reference signal of third frequency for the lock-in amplifier. The alternating current magnetic susceptibility measuring device provided by the invention has excellent performances such as high measurement accuracy and high signal-to-noise ratio at low frequency.

Description

technical field [0001] The invention relates to the field of magnetic susceptibility measurement, in particular to an AC magnetic susceptibility measurement device and a measurement method thereof. Background technique [0002] When an alternating magnetic field is applied to the magnetic sample, the magnetic sample itself will induce an alternating magnetic moment, and the ratio of the magnetic moment to the alternating magnetic field is the AC magnetic susceptibility of the magnetic sample. Since the magnetic moment induced by the magnetic sample under the alternating magnetic field oscillates with time, the magnetization dynamics information of the sample can be obtained from the alternating magnetic susceptibility. AC magnetic susceptibility is an important parameter to characterize the properties of matter, and it has a wide range of applications in the fields of spin glass, superparamagnetism, magnetic phase transition and superconductivity. [0003] figure 1 is a sc...

AI Technical Summary

Problems solved by technology

Therefore, the current AC susceptibility measurement device 1 using detection coils based on Faraday's law of electromagnetic induction cannot meet the needs of measuring the AC susceptibility of samples with small magnetic moments in the low frequency region.

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