More on phase-change materials for data storage

[Editors’ note: We invited Feng Rao and Wei Zhang, authors of work discussed in Ashley Smart’s Search story , to write a brief reply.]

Rao and Zhang reply: We are happy to answer the question posed by Kurt Rubin and Martin Chen in their last paragraph. In our work, ¹ scandium atoms were deposited randomly throughout the antimony telluride (Sb₂Te₃) thin film to serve as robust crystalline precursors for speeding up the intrinsic incubation of stable nuclei. If Sc atoms were deposited into discontinuous layers, potentially forming Sc₂Te₃, those layers may serve as a robust two-dimensional template to trigger rapid crystal growth. Such a scenario may be increasingly important as memory cells get miniaturized to achieve higher storage density. If ultrafast nucleation can be properly combined with rapid crystal growth via a stable 2D template, even faster memory writing speed can be expected. More research efforts should be invested in that exciting direction.