Design and characterization of a multicore Residence Times Difference (RTD) fluxgate magnetometer based on composite amorphous wire arrays

Amorphous wires show advantages of high permeability, low coercivity, and low hysteresis loss, therefore they are suitable as magnetic cores for fluxgate magnetometers. In RTD fluxgate magnetometers, the application of amorphous wires as magnetic cores has primarily focused on the use of a single wire. To achieve higher precision in weak magnetic field detection, further improvement in resolution is required. In this paper, we designed a multicore RTD fluxgate magnetometer based on composite amorphous wire arrays. We tested RTD fluxgate magnetometers with different numbers of amorphous wires (1, 2, 3, and 6 wires) as the magnetic cores. The test results showed that as the number of amorphous wires in the magnetic core increased, the resolution of the RTD fluxgate magnetometer improved from 5.15 nT to 0.17 nT, demonstrating that increasing the number of wires in the magnetic core effectively enhanced the resolution of the RTD fluxgate magnetometer.