Researchers clarify the microscopic origin of dissipation with graphene
Published Date: 2/18/2021
Source: phys.org
Mechanical sources of dissipation play a key role in modern physics, with applications that span nanomechanics, biomechanics, materials science, and quantum computing. In clocks and other vibrating mechanisms, energy loss is usually proportional to the speed of the vibrating object. But in special circumstances, where one resonant frequency of the resonator is exactly twice as high as another resonant frequency, these losses suddenly become much greater, as additional energy is lost through the coupling between these modes of vibration. With support from the European Research Council (ERC), associate professor Farbod Alijani and Ata Keşkekler Ph.D. student in the department of precision and microsystems engineering at TU Delft, tuned the interaction between the vibrational states of a graphene nanodrum in such a way that one mode vibrates exactly twice as fast as another. In doing so, they also showed that with this mechanism it is possible to control the damping force via the coupling strength between the two vibration modes.