The superconducting quantum interference device (SQUID) is one of the most sensitive detectors available for measurements of magnetic fields. Due to its unrivaled sensitivity, it has been employed in a variety of applications. One of the most successful application of SQUIDs is for measurements of the tiny magnetic fields produced by the firing neurons in a human brain. This application is known as magnetoencephalography (MEG) and is one of the topics of this thesis. In a state-of-the-art MEG system, a helmet shaped dewar incorporates several hundred SQUID sensors. Before the invention of the SQUID, the existence of magnetic fields produced by neural currents was proven by David Cohen in 1968 by using Faraday type detection with induction coils.
KeywordsSquid Magnetometer Superconducting Quantum Interference Device Squid Sensor Squid System Magnetic Field Sensitivity
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