A high-T/sub c/ SQUID based magnetophysiology system

We report on the present status of our high-T/sub c/ SQUID based system for measurements of room temperature samples. The main application of the system is magnetic recordings of signals in nerve tissue, i.e., magnetophysiology. We have fabricated four slotted SQUID sensors of two different designs. The best SQUID sensor shows an intrinsic white noise of 8.2 /spl mu//spl Phi//sub 0//Hz/sup 1/2/ and a corresponding magnetic field noise of 4.5 pT/Hz/sup 1/2/ at 77 K.