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arXiv · 2207.14078

Dirac/Weyl-node-induced oscillating Casimir effect

Katsumasa Nakayama·Kei Suzuki
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Abstract

The Casimir effect is a quantum phenomenon induced by the zero-point energy of relativistic fields confined in a finite-size system. This effect for photon fields has been studied for a long time, while the realization of counterparts for fermion fields in Dirac/Weyl semimetals is an open question. We theoretically demonstrate the typical properties of the Casimir effect for relativistic electron fields in Dirac/Weyl semimetals and show the results from an effective Hamiltonian for realistic materials such as Cd$_3$As$_2$ and Na$_3$Bi. We find an oscillation of the Casimir energy as a function of the thickness of the thin film, which stems from the existence of Dirac/Weyl nodes in momentum space. Experimentally, such an effect can be observed in thin films of semimetals, where the thickness dependence of thermodynamic quantities is affected by the Casimir energy.

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Katsumasa Nakayama, Kei Suzuki. 2022-07-28. Dirac/Weyl-node-induced oscillating Casimir effect. https://doi.org/10.1016/j.physletb.2023.138017

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