Research Projects

Coupled dynamics refers to the collective motion of two or more systems or modes that are mechanically coupled to each other. Nanoresonators fabricated using 2D materials such as graphene and other TMDCs are ideal to study these effects. Vibrational modes in these devices are strongly coupled to each other via strain. These coupled oscillations can lead to many interesting and useful phenomena, such nonlinear dynamics, synchronization, internal resonances. Understanding these effects in coupled systems has important implications for a wide range of applications, including sensing, signal processing, timing applications and energy harvesting. The aim of the proposed research project is to investigate the coupled dynamics in 2D nanoresonators and develop a comprehensive understanding of coupling between different modes and their effect on their dynamics. We’ll use a combination of experimental and numerical techniques to investigate the motion of coupled nanoresonators and identify the effect of mode coupling on nonlinear coefficients and linear and nonlinear damping. In this proposal, we are proposing a novel way of controlling strain and hence coupling. The crux of the proposal is to fabricate 2D nanoresonators on a thin silicon diaphragm. The diaphragm provides a simple and elegant way to change the strain at the device. The thin silicon diaphragm can be strained using either a pressure difference across the chip or a piezo transducer. This bending of the substrate translates into strain at the 2D nanoresonator. This strain modulation at the device can be used to tune the coupling between different modes of the device. It is also possible to orient the 2D nanoresonators relative to the radial direction of the diaphragm to control the effect of strain on the coupling. Furthermore, we have previously demonstrated that the nonlinear coefficients in 2D nanoresonators can be controlled using electrostatic gate voltages. These independent control over the parameters of the device would utilized to perform a detailed study of the dynamics of coupled systems. We expect the study to clarify several outstanding questions in the dynamics of the 2D nanoresonators including the role of coupling in the damping, nonlinear coefficients and the effect these will have on phenomenon such as synchronization and internal resonances. The project outcomes will have applications in many fields, including communication, sensing, and computation.

2D nanoresonator, nonlinear dynamics, mode coupling, mechanical resonators