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arXiv · 2004.12456

Casimir forces on deformed fermionic chains

Begoña Mula·Silvia N. Santalla·Javier Rodríguez-Laguna
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Abstract

We characterize the Casimir forces for the Dirac vacuum on free-fermionic chains with smoothly varying hopping amplitudes, which correspond to (1+1)D curved spacetimes with a static metric in the continuum limit. The first-order energy potential for an obstacle on that lattice corresponds to the Newtonian potential associated to the metric, while the finite-size corrections are described by a curved extension of the conformal field theory predictions, including a suitable boundary term. We show that, for weak deformations of the Minkowski metric, Casimir forces measured by a local observer at the boundary are metric-independent. We provide numerical evidence for our results on a variety of (1+1)D deformations: Minkowski, Rindler, anti-de Sitter (the so-called rainbow system) and sinusoidal metrics.

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Begoña Mula, Silvia N. Santalla, Javier Rodríguez-Laguna. 2020-04-26. Casimir forces on deformed fermionic chains. https://doi.org/10.1103/physrevresearch.3.013062

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