We demonstrate the first detection of brain magnetic fields evoked by auditory stimulation with a non-cryogenic optical magnetometer. We use a spin-exchange-relaxation-free (SERF) alkali-metal magnetometer and map magnetic fields using multi-channel photodiode arrays. This first-generation system has a magnetic noise level of 3.5 fT/Hz1/2 at 10 Hz, similar to the state-of-the-art cryogenic systems. Absence of a cryogenic dewar eliminates magnetic Johnson noise and allows the use of compact magnetic shields with a high shielding factor.
All Science Journal Classification (ASJC) codes
- Atomic magnetometer
- Auditory evoked response