Demonstration of Angle-Dependent Casimir Force between Corrugations

Abstract

The normal Casimir force between a sinusoidally corrugated gold coated plate and a sphere was measured at various angles between the corrugations using an atomic force microscope. A strong dependence on the orientation angle of the corrugation is found. The measured forces were found to deviate from the proximity force approximation and are in agreement with the theory based on the gradient expansion including correlation effects of geometry and material properties. We analyze the role of temperature. The obtained results open new opportunities for control of the Casimir effect in micromechanical systems.

Constraints on corrections to Newtonian gravity from two recent measurements of the Casimir interaction between metallic surfaces

“…The advantages of using magnetic materials are elucidated. Section III is devoted to the experiment with corrugated surfaces [30]. Here, we derive an expression for the Yukawa-type force in configurations with different angles between corrugations.…”

“…In the second experiment of our interest here [30] the static AFM was used to measure the Casimir force between a plate and a sphere both with sinusoidally corrugated surfaces coated with nonmagnetic metal Au. The unusual feature of this experiment, as compared with earlier performed experiments with corrugated surfaces, is that the Casimir force was measured at various angles between the longitudinal corrugations on both bodies.…”

Calculating Casimir interactions for periodic surface-relief gratings using theCmethod

“…As the experiments have become more sensitive, it has become necessary to do the theoretical analysis outside the range of validity of the PFA. Recently a derivative expansion (DE) approach has been introduced [16][17][18], which reproduces the PFA and gives the next order correction, and which has successfully explained a number of new recent experiments [13,14]. The first theoretical calculation of the Casimir force between geometrically patterned surfaces not using the PFA was reported in 2001 [19,20], which described the normal and lateral forces between two aligned corrugated surfaces in terms of a perturbative expansion in the profile height.…”

“…There have been a number of experiments showing that the magnitude of the Casimir force could be varied by changing the surface geometry of the interacting objects [5][6][7][8][9][10][11][12][13][14]. To investigate the impact of curvature and corrugation, the Casimir forces have been measured between a sphere and a sinusoidal grating [5] and between two corrugated surfaces for both aligned [6,7] and crossed [13,14] corrugations.…”

“…To investigate the impact of curvature and corrugation, the Casimir forces have been measured between a sphere and a sinusoidal grating [5] and between two corrugated surfaces for both aligned [6,7] and crossed [13,14] corrugations.…”