10th Internatıonal Conference On Computatıonal And Experımental Scıence And Engıneerıng (ICCESEN-2023), Antalya, Turkey, 27 - 30 October 2023, pp.1
In this paper, casimir force sensitivity is investigated by utilizing a micro-cantilever under the driving forces in heptamodal operations. A forced Van der Pol-Rayleigh-Helmholtz oscillator is used to describe the nonlinear dynamics of the micro-cantilever which is subject to the excitation and casimir forces simultaneously. Demonstrating the effectiveness of the heptamodal operations, single- and tetramodal-frequency excitation schemes are also applied separately to resonate the micro-cantilever at the fundamental and higher eigenmodes. The oscillation observables of the externally driven micro-cantilever are determined in the presence of the casimir forces in the separation distance range of 200-800 nm. Remarkable variations in amplitude ratio, phase shift, and frequency shift for different effective masses of the micro-cantilever are explored for the higher eigenmodes. In this current work, the maximum phase shift response of around 150 degrees at the sixth eigenmode is achieved using heptamodal-frequency excitation of the lightest micro-cantilever at the separation distance of 200 nm. Thus, implementing heptamodal-frequency excitation schemes has considerable potential to improve the phase shift sensitivity to casimir forces when compared with other excitation schemes. Additionally, the parameters of the nonlinear oscillator determine significantly the patterns of the time-domain sensitivities to the external forces. Correspondingly, displacements of the micro-cantilever under the driving and casimir forces at different eigenmodes are obtained to investigate diverse system nonlinearities. Furthermore, the virial and dissipated power are also determined for different effective masses of the micro-cantilever to explain the energy dissipation process in the measurement of casimir forces. Therefore, in the present work, the observable responses and energy quantities for particular system nonlinearities are introduced to be utilized for nanometrological applications.