Magnetic Field Meter Based on CMR-B-Scalar Sensor for Measurement of Microsecond Duration Magnetic Field Pulses

Area of Science:

• Physics
• Materials Science
• Electrical Engineering

Background:

• Accurate measurement of high-amplitude pulsed magnetic fields is critical for various scientific and industrial applications.
• Existing methods often face challenges with interference, orientation dependence, and limited dynamic range.

Purpose of the Study:

• To develop and validate a novel system for precise measurement of pulsed magnetic fields with high amplitude and microsecond duration.
• To leverage colossal magnetoresistance (CMR) materials for orientation-independent magnetic field sensing.
• To minimize interference and parasitic effects during measurement.

Main Methods:

• A system comprising a probe with a La-Sr-Mn-O thin film sensor exhibiting CMR and a specialized measurement unit was designed.
• Two versions of the measurement unit were developed, differing in amplifier integration for sensor distances <0.5 m and >1 m.
• Bipolar pulsed voltage was applied to the sensor to mitigate electromotive force induction.
• Data acquisition involved a fiber optic link to a PC with custom processing software.

Main Results:

• The La-Sr-Mn-O CMR sensor demonstrated precise, orientation-independent magnetic field measurement capabilities.
• Optimized film compositions were tested successfully in pulsed magnetic fields.
• The system effectively measured pulsed magnetic fields up to 15 Tesla with pulse durations of 20-30 microseconds.
• Minimal interference was achieved through system design and bipolar voltage application.

Conclusions:

• The developed system provides a robust and accurate solution for measuring high-amplitude, microsecond pulsed magnetic fields.
• The use of CMR manganite films offers a significant advancement in magnetic field sensing technology.
• The system's effectiveness was confirmed through rigorous testing up to 15 T, demonstrating its potential for demanding applications.