Ultrahigh Casimir interaction torque in nanowire systems
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Updated: May 10, 2026

Magnetic Tweezers for the Measurement of Twist and Torque
Published on: May 19, 2014
Tiago A Morgado1, Stanislav I Maslovski, Mário G Silveirinha
1University of Coimbra, Department of Electrical Engineering–Instituto de Telecomunicações, 3030-290 Coimbra, Portugal.
Abstract:
We study the Casimir torque arising from the quantum electromagnetic fluctuations due to the interaction of two interfaces in a system formed by a dense array of metallic nanorods embedded in dielectric fluids. It is demonstrated that as a consequence of the ultrahigh density of photonic states in the nanowire array it is possible to channel the quantum fluctuations, and thereby boost the Casimir torque by several orders of magnitude as compared to other known systems (e.g., birefringent parallel plates).
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