Science Daily January 29, 2020
An international team of researchers (USA – NIST, University of Maryland, Japan, Canada) created weakly coupled quantum dots by using the ultrasharp tip of a scanning tunneling microscope as a stylus hovering the tip above an ultracold sheet of graphene briefly increasing the voltage of the tip penetrating through the graphene into an underlying layer of boron nitride. It stripped electrons from atomic impurities in the layer and created electric charge which corralled freely floating electrons in the graphene, confining them to a tiny energy well. When a magnetic field of 4 to 8 tesla was applied, it dramatically altered the shape and distribution of the orbits so that the electrons now resided within two sets of concentric rings within the original well behaving as if they were weakly coupled quantum dots. Such ”coupled” quantum dots could serve as a qubit, the fundamental unit of information for a quantum computer…read more. TECHNICAL ARTICLE