Photomelting of selenium at low temperature

We report on a photoinduced phenomenon in solids, namely, photomelting at low temperature. We have found that both trigonal and amorphous selenium can be molten by illumination with light at a temperature of ∼77 K. This phenomenon is pure optical (athermal) and it is associated with light-induced breaking of the interchain (intermolecular) bonds in selenium. The photomelting is important for basic science (as an example of photoinduced phase transition in condensed matter and as a key photoinduced phenomenon in selenium and related materials) and for applications (as a tool for fine manipulation with shape of solids by light at low temperatures).