Spin Lifetime in Small Electron Spin Ensembles Measured by Magnetic   Resonance Force Microscopy
  Magnetic Resonance Force Microscopy can enable nanoscale imaging of spin lifetime. We report temperature dependent measurements of the spin correlation time $\tau_m$ of the statistical fluctuations of the spin polarization---the spin noise---of ensembles containing $\sim 100$ electron spins by this technique. Magneto-mechanical relaxation due to spin-cantilever coupling was controlled and spurious mechanisms that can affect the spin correlation time of the microscopic signal were characterized. These measurements have ramifications for optimizing spin sensitivity, understanding local spin dynamics and for nanoscale imaging. 
Kin Chung Fong, Micheal R. Herman, Palash Banerjee, Denis V. Pelekhov,   Chris Hammel
cond-mat.mes-hall