Spin friction seen for a single atom

An international team of researchers says that it has measured the spin-dependent component of friction of a single atom as it slides across a magnetic surface, for the first time. The team used a combination of spin-polarized scanning tunnelling microscopy and single-atom manipulation to push individual magnetic atoms over a magnetic template. Comparing experimental results with simulations, the researchers were able to conclusively say that spin-dependent friction contributes substantially to the overall frictional force experienced by an atom. They say that their results provide an essential step towards developing a fundamental theory of friction.