Thermally-modulated dissipation dilution in 2D NEMS resonators with explicit model and temperature-stable damping.

Strain-diluted dissipation has emerged as a promising technique to modulate the quality (Q) factor of resonant nanoelectromechanical systems (NEMS). However, comprehensive understanding and precise control of this effect under varying temperatures have remained elusive. Here we investigate the temperature-modulated dissipation dilution mechanisms in two-dimensional (2D) NEMS resonators. We develop an explicit temperature-dependent dissipation dilution model highlighting the roles of thermally-induced strain and temperature fluctuations during vibration, which well captures experimental observations: with temperature increasing from 77 K to 355 K, Q factor in graphene resonators first decreases and then increases, while that in molybdenum disulfide (MoS2) resonators monotonically decreases. Furthermore, based on the model, we design a graphene-MoS2 heterostructure NEMS resonator with near-zero effective thermal expansion, which experimentally exhibits high temperature stability in both frequency and Q factor. Our results advance the understanding of dissipation dilution mechanisms and pave the way for developing thermally-stable resonant transducers and logic components.