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arXiv · 0902.2961

Critical Casimir force in slab geometry with finite aspect ratio: analytic calculation above and below $T_c$

Volker Dohm
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Abstract

We present a field-theoretic study of the critical Casimir force of the Ising universality class in a $d$-dimensional ${L_\parallel^{d-1} \times L}$ slab geometry with a finite aspect ratio $ρ= L/L_\parallel$ above, at, and below $T_c$. The result of a perturbation approach at fixed dimension $d=3$ is presented that describes the dependence on the aspect ratio in the range $ρ\gtrsim 1/4$. Our analytic result for the Casimir force scaling function for $ρ= 1/4$ agrees well with recent Monte Carlo data for the three-dimensional Ising model in slab geometry with periodic boundary conditions above, at, and below $T_c$.

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Volker Dohm. 2009-02-19. Critical Casimir force in slab geometry with finite aspect ratio: analytic calculation above and below $T_c$. https://doi.org/10.1209/0295-5075/86/20001

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