High-Frequency Carrier-Type Magnetic Field Sensor with a Sub-pT Resolution Using a Magnetic Film and a Transmission Line

Abstract

We developed a very sensitive high-frequency carrier-type magnetic field sensor with a sub-pT resolution using a resonating transmission line. Meander-type sensor elements using amorphous CoNbZr films were fabricated. We obtained a magnetic field resolution of 7.4 x 10^-13 T/Hz^1/2 at 501 kHz. The detectable magnetic field was limited bythe noise caused by nonlinear magnetic excitation. We analyzed the quality factor of the resonance for enhancementof the signal-to-noise ratio.