Researchers from Kiel University and European colleagues designed and fabricated single molecular spin switches. The newly developed molecules feature stable spin states and do not lose their functionality upon adsorption on surfaces.
The researchers say that the spin states of the new compounds are stable for at least several days. The new molecules have three properties that are coupled with each other in such a feedback loop: their shape (planar or flat), the proximity of two subunits, called coordination (yes or no), and the spin state (high-spin or low-spin). Thus, the molecules are locked either in one or the other state. Upon sublimation and deposition on a silver surface, the switches self-assemble into highly ordered arrays. Each molecule in such an array can be separately addressed with a scanning tunneling microscope and switched between the states by applying a positive or negative voltage.