Torque on birefringent plates induced by quantum fluctuations

Journal Article · Fri Apr 01 04:00:00 EST 2005 · Physical Review. A

DOI:https://doi.org/10.1103/PhysRevA.71.042102· OSTI ID:20653249

Munday, Jeremy N ^[1]; Iannuzzi, Davide; Capasso, Federico ^[2]; Barash, Yuri ^[3]

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1. Harvard University, Department of Physics, Cambridge, Massachusetts 02138 (United States)
2. Harvard University, Division of Engineering and Applied Sciences, Cambridge, Massachusetts 02138 (United States)
3. Institute of Solid State Physics, Russian Academy of Sciences, Institutskaya ul. 2, Chernogolovka, Moscow region 142432 (Russian Federation)

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{approx_equal}100 nm, the maximum torque (at {theta}={pi}/4) is of the order of {approx_equal}10{sup -19} N 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.

• OSTI ID: 20653249
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 4 Vol. 71; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
74 ATOMIC AND MOLECULAR PHYSICS
ANISOTROPY
BARIUM COMPOUNDS
CALCITE
DISTANCE
ETHANOL
FLUCTUATIONS
LIQUIDS
PLATES
QUANTUM MECHANICS
QUARTZ
TITANATES
TORQUE
VAN DER WAALS FORCES