A MINIATURE MAGNETOMETER BASED ON THE SUPERCONDUCTING QUANTUM INTERFERENCE DEVICE WITH DIRECT READOUT ELECTRONICS

A novel miniature superconducting quantum interference device magnetom eter with direct readout electronics has been developed. A high flux-t o-voltage transfer factor of up to 2500 mu V/phi(0) is achieved withou t additional positive feedback (phi(0) is the flux quantum). A flux re solution of 8x10(-7)phi(0)/Hz(1/2), corresponding to a magnetic moment sensitivity of approximately 2x10(-20) A m(2)/Hz(1/2), has been measu red. This magnetometer can be used to study the dynamic magnetization properties (including nuclear magnetic resonance and magnetic resonanc e imaging) of micron and submicron size particles and for high-resolut ion surface magnetometry. (C) 1997 American Institute of Physics.