Fast nuclear spin hyperpolarization of phosphorus in silicon
  We experimentally demonstrate a method for obtaining nuclear spin hyperpolarization, that is, polarization significantly in excess of that expected for a thermal equilibrium. By exploiting a modified Overhauser process, we obtain more than 68% nuclear anti-polarization of phosphorus donors in silicon. This polarization is reached with a time constant of ~150 seconds, at a temperature of 1.37 K and a magnetic field of 8.5 T. The ability to obtain such large polarizations is discussed with regards to its significance for quantum information processing and magnetic resonance imaging. 
D. R. McCamey, J. van Tol, G. W. Morley, C. Boehme