Dynamics Of Paramagnetic Spins

Magnetic Resonance Force Microscopy (MRFM) is a challenging yet incredibly sensitive tool for characterizing and imaging magnetic materials down to the nanoscale. It combines the technology of scanned probe microscopy with the powerful spectral techniques of magnetic resonance. The MRFM can measure very small spin ensembles, down to a single electron spin, and the measurements are performed at thermal equilibrium. Instead of perturbing the polarization away from equilibrium, the 'spin noise' or statistical spin fluctuations are used to generate a force signal. Here I show MRFM measurements on a nanoscale 'spin wire', which is a narrow, high spin density region implanted in a diamond substrate. The spin wire measurements reveal an interesting interplay between the transport and lifetime of spins confined within the nanoscale diamond wire which are relevant for the development of nanoscale spintronics. Additionally, I show measurements which resolve the hyperfine spectrum of the defects in the spin wire by measuring less than 100 net spins.