dorsal/arxiv
View SchemaOn the torque on birefringent plates induced by quantum fluctuations
| Authors | Davide Iannuzzi, Jeremy N. Munday, Yuri Barash, Federico Capasso |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0410136 |
| URL | https://arxiv.org/abs/quant-ph/0410136 |
| DOI | 10.1103/PhysRevA.71.042102 |
| Journal | Phys. Rev. A71, 042102 (2005) (slightly different version) |
Abstract
We present detailed numerical calculations of the mechanical torque induced by quantum fluctuations on two parallel birefringent plates with in plane optical anisotropy, separated by either vacuum or a liquid (ethanol). The torque is found to vary as $\sin(2\theta)$, where $\theta$ represents the angle between the two optical axes, and its magnitude rapidly increases with decreasing plate separation $d$. For a 40 $\mu$m diameter disk, made out of either quartz or calcite, kept parallel to a Barium Titanate plate at $d\simeq 100$ nm, the maximum torque (at $\theta={\pi\over 4}$) is of the order of $\simeq 10^{-19}$ N$\cdot$m. We propose an experiment to observe this torque when the Barium Titanate plate is immersed in ethanol and the other birefringent disk is placed on top of it. In this case the retarded van der Waals (or Casimir-Lifshitz) force between the two birefringent slabs is repulsive. The disk would float parallel to the plate at a distance where its net weight is counterbalanced by the retarded van der Waals repulsion, free to rotate in response to very small driving torques.
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"abstract": "We present detailed numerical calculations of the mechanical torque induced\nby quantum fluctuations on two parallel birefringent plates with in plane\noptical anisotropy, separated by either vacuum or a liquid (ethanol). The\ntorque is found to vary as $\\sin(2\\theta)$, where $\\theta$ represents the angle\nbetween the two optical axes, and its magnitude rapidly increases with\ndecreasing plate separation $d$. For a 40 $\\mu$m diameter disk, made out of\neither quartz or calcite, kept parallel to a Barium Titanate plate at $d\\simeq\n100$ nm, the maximum torque (at $\\theta={\\pi\\over 4}$) is of the order of\n$\\simeq 10^{-19}$ N$\\cdot$m. We propose an experiment to observe this torque\nwhen the Barium Titanate plate is immersed in ethanol and the other\nbirefringent disk is placed on top of it. In this case the retarded van der\nWaals (or Casimir-Lifshitz) force between the two birefringent slabs is\nrepulsive. The disk would float parallel to the plate at a distance where its\nnet weight is counterbalanced by the retarded van der Waals repulsion, free to\nrotate in response to very small driving torques.",
"arxiv_id": "quant-ph/0410136",
"authors": [
"Davide Iannuzzi",
"Jeremy N. Munday",
"Yuri Barash",
"Federico Capasso"
],
"categories": [
"quant-ph"
],
"doi": "10.1103/PhysRevA.71.042102",
"journal_ref": "Phys. Rev. A71, 042102 (2005) (slightly different version)",
"title": "On the torque on birefringent plates induced by quantum fluctuations",
"url": "https://arxiv.org/abs/quant-ph/0410136"
},
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