Study: Phase-change memory

Phase-change memory (PCM) could be the next big breakthrough in computer memory. In theory, this type of memory will store information by rearranging the atoms in a solid memory bit, allowing fast, non-volatile memory storage. One problem is that these phase changes are poorly understood, but a recent study from the University of Pennsylvania could help engineers get a few steps closer. Atoms in a solid can be arranged in one of two general ways: in a crystal lattice displaying order across large portions of the sample, or randomly arranged ("amorphously") with little or no overall order. The latter case offers significantly higher resistance because of the more random path electrons must travel through the material. Previously, scientists thought the only way to transition between these two states is melting, but the Penn researchers have shown that melting is not the only way.