The thinnest materials that can be produced today have the thickness of a single atom. These materials – known as two-dimensional materials – exhibit properties that are very different compared with their bulk three-dimensional counterparts. Until recently, 2-D materials were produced and manipulated as films on the surface of some suitable 3-D substrate. Working in collaboration with a team from the Leibniz Institute for New Materials, a group of physicists at Saarland University, led by Professor Uwe Hartmann, has for the first time succeeded in characterizing the mechanical properties of free-standing single-atom-thick membranes of graphene. The measurements were performed using scanning tunnelling microscopy (STM). The researchers have published their results in the specialist journal Nanoscale.