Dieter Suter: "Magnetic resonance with small samples: principles and applications"

Magnetic resonance with small samples: principles and applications

Magnetic resonance provides valuable information on virtually every type of material, in physics, chemistry, medicine and other fields. In many applications, its usefulness is only limited by its inherently low sensitivity. If the amount of available sample is limited, it becomes difficult to acquire a signal that exceeds the thermal noise of the detector. In these cases, it is often possible to increase the signal by several orders of magnitude by adapting the resonator to the available sample. We show examples from NMR and EPR, where miniaturized resonators allow one to measure samples with dimensions in the nanometer to micrometer range. Another possible approach consists in increasing the polarization, e.g. by optical pumping, and / or using detection techniques that do not rely on Faraday´s law of induction.