Nanomechanical dissipation, experienced by the tip of Force Microscopy (AFM) instruments, provides an innovative probe of the physics of classical and quantum materials, solids and surfaces. Experimental and conceptual advances by exploiting and adapting advanced AFM techniques were made, especially the ultra-sensitive pendulum-AFM (p-AFM), to detect collective phenomena, including structural, electronic and magnetic phase transitions. So far, dissipation spectroscopy was applied mostly at the equilibrium physics of 3D classical solids. Our goal is to go a step beyond by exploring nanomechanical dissipation to sense much weaker effects caused by non-equilibrium perturbations, during nanomanipulations or involving quantum effects in ground-breaking case studies. The examples of those are the measurements of the energy dissipation in strongly correlated electron system of twisted bilayer graphene or study of imperceptible wind force exerted on a noncontact tip by a thermal or electrical current in the surface below, or the minute mechanical cost of creating and dismantling a single spin Kondo state, or a topological surface state. The goal of these investigations is to get a more fundamental understanding of energy dissipation and friction processes, as well as to link them to generally understood solid state surface phenomena. Friction and energy loss are of great concern for the society, because it is the main source of energy losses of all kind of machines, including significant concern for future electronics. The main objective is to explore energy loss mechanisms on a local scale with emphasis on non-classical effects. Identifying new methods of spectroscopy is of wider scientific and technological interest. An important methodological goal of our project is to demonstrate and consolidate further both experimentally and theoretically the potential of nanotribological and nanomechanical dissipation in performing, often without physically touching a material's surface, a delicate form of spectroscopy. Covering disparate phenomena – electronic and magnetic, structural and phononic, on or off-equilibrium, static or dynamic – that occur inside or at the surface of a solid material. With that perspective, theoretical calculations, simulations and predictions form an important part of the project, regarding ongoing and planned experiments in the group, as well as wider range explorations of tribological and related physical problems in a broader context.
