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arXiv · 1506.03531

Casimir--Polder force between anisotropic nanoparticles and gently curved surfaces

Giuseppe Bimonte·Thorsten Emig·Mehran Kardar
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Abstract

The Casimir--Polder interaction between an anisotropic particle and a surface is orientation dependent. We study novel orientational effects that arise due to curvature of the surface for distances much smaller than the radii of curvature by employing a derivative expansion. For nanoparticles we derive a general short distance expansion of the interaction potential in terms of their dipolar polarizabilities. Explicit results are presented for nano-spheroids made of SiO$_2$ and gold, both at zero and at finite temperatures. The preferred orientation of the particle is strongly dependent on curvature, temperature, as well as material properties.

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Giuseppe Bimonte, Thorsten Emig, Mehran Kardar. 2015-06-11. Casimir--Polder force between anisotropic nanoparticles and gently curved surfaces. https://doi.org/10.1103/physrevd.92.025028

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