Qualitative chirality effects on the Casimir-Lifshitz torque with liquid crystals

Abstract

We model a cholesteric liquid crystal as a planar uniaxial multilayer system, where the orientation of each layer differs slightly from that of the adjacent one. This allows us to analytically simplify the otherwise acutely complicated calculation of the Casimir-Lifshitz torque. Numerical results differ appreciably from the case of nematic liquid crystals, which can be treated like bloc birefringent media. In particular, we find that the torque deviates considerably from its usual sinusoidal behavior as a function of the misalignment angle. In the case of a birefringent crystal faced with a cholesteric liquid one, the Casimir-Lifshitz torque decreases more slowly as a function of distance than in the nematic case. In the case of two cholesteric liquid crystals, either in the homochiral or in the heterochiral configuration, the angular dependence changes qualitatively as a function of distance. In all considered cases, finite pitch length effects are most pronounced at distances of about 10 nm.

References in corpus (14)

• The Casimir effect within scattering theory
• Generalized 4 $\times$ 4 Matrix Formalism for Light Propagation in Anisotropic Stratified Media: Study of Surface Phonon Polaritons in Polar Dielectric Heterostructures
• Casimir-Lifshitz Theory and Metamaterials
• On the torque on birefringent plates induced by quantum fluctuations
• Influence of random roughness on the Casimir force at small separations
• Roughness correction to the Casimir force at short separations: Contact distance and extreme value statistics
• Significance of the Casimir force and surface roughness for actuation dynamics of MEMS
• Enhanced chiral discriminatory van der Waals interactions mediated by chiral surfaces
• Roughness correction to the Casimir force beyond perturbation theory
• An alternative calculation of the Casimir forces between birefringent plates
• Rotation of a liquid crystal by the Casimir torque
• The Casimir effect as a sum-over-modes in dissipative systems
• Van der Waals torque and force between anisotropic topological insulator slabs
• Maxwell Eigenmode approach to the Casimir-Lifshitz Torque

Cited by in corpus (1)

• Twisted bilayered graphenes at magic angles and Casimir interactions: correlation-driven effects