Spin-Droplet State of an Interacting 2D Electron System
  We report thermodynamic magnetization measurements of two-dimensional electrons in several high mobility Si metal-oxide-semiconductor field-effect transistors. We provide evidence for an easily polarizable electron state in a wide density range from insulating to deep into the metallic phase. The temperature and magnetic field dependence of the magnetization is consistent with the formation of large-spin droplets in the insulating phase. These droplets melt in the metallic phase with increasing density and temperature, although they survive up to large densities. 
N. Teneh, A. Yu. Kuntsevich, V. M. Pudalov, M. Reznikov
cond-mat.str-el cond-mat.dis-nn