Field-induced nucleation in phase change memory

A theory of field-induced crystal nucleation is developed and verified experimentally for the case of switching in nanoglasses of phase change memory. For symmetry-breaking strong electric fields, it predicts needle-shaped crystallites with nucleation barriers lower than that of spherical nuclei and a strong field dependent. We have observed bias dependent switching for times and temperatures far,beyond those typically reported and supportive of our predictions, in particular, switching time exponential in voltage and temperature.