Measuring the Casimir Forces with an Adhered Cantilever: Analysis of Roughness and Background Effects

Universe

VitalyB. Svetovoy¹  IvanA. Soldatenkov²  AnastasiyaA. Yakovenko² 

[1] A. N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Leninsky Prospect 31 Bld. 4, 119071 Moscow, Russia;Ishlinsky Institute for Problems in Mechanics, Russian Academy of Sciences, Prospect Vernadskogo, 101-1, 119526 Moscow, Russia;

关键词: Casimir forces;    non-Newtonian forces;    short distances;    surface roughness;    adhered cantilever;    contact mechanics;   

DOI  :  10.3390/universe7030064

来源: DOAJ

【 摘 要 】

Technological progress has made possible precise measurements of the Casimir forces at distances less than $100$nm. It has enabled stronger constraints on the non-Newtonian forces at short separations and improved control of micromechanical devices. Experimental information on the forces below $30$nm is sparse and not precise due to pull-in instability and surface roughness. Recently, a method of adhered cantilever was proposed to measure the forces at small distances, which does not suffer from the pull-in instability. Deviation of the cantilever from a classic shape carries information on the forces acting nearby the adhered end. We calculate the force between a flat cantilever and rough Au plate and demonstrate that the effect of roughness dominates when the bodies approach the contact. Short-distance repulsion operating at the contact is included in the analysis. Deviations from the classic shape due to residual stress, inhomogeneous thickness of the cantilever, and finite compliance of the substrate are analysed. It is found that a realistic residual stress gives a negligible contribution to the shape, while the finite compliance and inhomogeneous thickness give measurable contributions that have to be subtracted from the raw data.

【 授权许可】

Unknown