Stable Levitation and Alignment of Compact Objects by Casimir Spring Forces

Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Physical Review Letters (Impact Factor: 7.73). 02/2010; 104(7):070405. DOI: 10.1103/PhysRevLett.104.070405
Source: arXiv

ABSTRACT We investigate a stable Casimir force configuration consisting of an object contained inside a spherical or spheroidal cavity filled with a dielectric medium. The spring constant for displacements from the center of the cavity and the dependence of the energy on the relative orientations of the inner object and the cavity walls are computed. We find that the stability of the force equilibrium-unlike the direction of the torque-can be predicted based on the sign of the force between two slabs of the same material.

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    Physical Review Letters 11/2013; 111(18):180402. DOI:10.1103/PhysRevLett.111.180402 · 7.73 Impact Factor
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    Physical Review B 01/2014; 89(20). DOI:10.1103/PhysRevB.89.201407 · 3.66 Impact Factor
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    ABSTRACT: It is shown that the electromagnetic Casimir force acting on a conducting body (e.g., a realistic metallic piston) sliding in a background formed by cut silver nanorods (with the body perforated by the nanorods) is repulsive at distances larger than the separation of the nanorods, even if the host material of the nanorods is air. It is demonstrated that the physical origin of this effect is in essence related to Boyer’s prediction that magnetic and conducting walls repel each other. Indeed, we show that from the point of view of an observer inside the nanowire structure, the interface formed by severing the nanowires mimics accurately the behavior of a magnetic wall for P-polarized waves. In contrast to other piston configurations reported in the literature, the Casimir interaction in the nanowire background is an ultralong-range force that decays with the distance to the nearby interface as 1/a2.
    Physical Review A 02/2011; 83(2):022508. DOI:10.1103/PhysRevA.83.022508 · 2.99 Impact Factor

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