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Electrostatically gated dissipation control in two-dimensional nanoelectromechanical resonators via strain-amplitude antagonism for record 928% Q tunability
Resonators based on nanoelectromechanical systems (NEMS) using two-dimensional (2D) materials with high-quality factors and excellent electrical control are critical for tunable coherent phonon dynamics, resonant sensors and wireless communications. However, their performance is fundamentally limited by the lack of a unified framework governing energy dissipation mechanisms and their electrical tunability. Here, we synergistically modulate both static tensile strain (") and dynamic vibration amplitude (z) through electrostatic gating, achieving deterministic control over thermoelastic dissipation pathways in 2D doubly-clamped resonators. By combining analytical modeling with experimentalmeasurements on MoS2 and graphene devices, we demonstrate that " suppresses dissipation, while z amplifies dissipation. The interaction of these effects can control the dependence of Q on DC gate voltage VG, including the non-monotonic trend and the record-breaking tunability range of Q/Q = 928%. Crucially, we identify a critical regime where the strain-to-amplitude sensitivity ratio (@"/@VG)/(@z/@VG) governs the Q-VG relationship polarity, resolving long-standing discrepancies in literature. This universal framework demonstrates that through the control of initial strain and vibration amplitude, it is feasible to achieve the desired modulation of Q, thus paving the way for 2D NEMS applications in topological phononic circuits, quantum-limited mass sensing, and adaptive on-chip signal processing.