Master's thesis defence by Hans Christian Stærkind

Magnetometry for biomedical applications

Abstract
Electrical signals in the brain, the heart, and the nervous system, generate tiny mag-
netic fields. The advent of highly sensitive magnetometers has opened the field of bio- magnetometry, where magnetic measurements are used to infer the electric activity inside
living organisms.

Electrical measurements are essential for many different kinds of medical diagnostics.
Maybe in the future, magnetic measurements can replace electrical measurements, and
enable new diagnostic possibilities.

We report the first measurement of the magnetic field from a nerve with an optical
magnetometer. We measure a magnetic field with a peak-to-peak value of 20 pT, and we
are able to detect the signal with the sensor as far away as 4 mm.

This thesis describes in detail the characterization of anti-relaxation coated atomic vapour cells, the working of our magnetometer, and the measurements of the nerve magnetic
field.

Supervisor: Prof. Eugene Polzik