Quantum Wigner crystal in a two-dimensional electron system?

The spin susceptibility of strongly correlated electrons in a low-disorder two-dimensional electron system exhibits a sharp increase tending to a divergence at a finite electron density.  Surprisingly, this behavior is due to the divergence of the effective mass rather than that of the g-factor.  Our results provide clear evidence for an interaction-induced phase transition to a new phase that may be a precursor phase or a direct transition to the long sought-after Wigner solid.