Temperature-Dependence of the Resistivity of a Dilute 2D Electron System   in High Parallel Magnetic Field
  We report measurements of the resistance of silicon MOSFETs as a function of temperature in high parallel magnetic fields where the 2D system of electrons has been shown to be fully spin-polarized. A magnetic field suppresses the metallic behavior observed in the absence of a magnetic field. In a field of 10.8 T, insulating behavior is found for densities up to n_s approximately 1.35 x 10^{11} cm^{-2} or 1.5 n_c; above this density the resistance is a very weak function of temperature, varying less than 10% between 0.25 K and 1.90 K. At low densities the resistance goes to infinity more rapidly as the temperature is reduced than in zero field and the magnetoresistance diverges as T goes to 0. 
K. M. Mertes, Hairong Zheng, S. A. Vitkalov, M. P. Sarachik, and T. M.   Klapwijk