We studied the properties of a magnetometer using high-Tc superconducting coils and an inductance modulation scheme. First, we obtained analytical expressions for the responsivity and magnetic field noise of the magnetometer that could be used for the design of a magnetometer. Next, a prototype magnetometer was fabricated and its performance was measured in liquid nitrogen. It was observed that the measured results agreed well with the calculated results, which indicated the validity of the present design method. We obtained a magnetic field noise of 0.8 pT/Hz1/2 above 25 Hz when using a pickup coil with 50 turns and an average diameter of 25 mm. At low frequencies, the field noise increased when decreasing the frequency, and reached 9 pT/Hz1/2 at 1 Hz. We also discuss the improvement of the magnetometer performance when the size of the pickup coil is increased.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics