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Casimir force at both nonzero temperature and finite conductivity
M Bordag1, B Geyer, G L Klimchitskaya
1Institute for Theoretical Physics, Leipzig University, Augustusplatz 10/11, 04109 Leipzig, Germany. Michael.Bordag@itp.uni-leipzig.de
Physical Review Letters
|September 16, 2000
Summary
This study investigates how temperature and finite conductivity affect the Casimir force in real metals. We developed perturbation theory and compared it with computations for parallel plates and sphere-plate systems.
Area of Science:
- Condensed matter physics
- Quantum field theory
Background:
- The Casimir force, a quantum electrodynamic effect, is crucial in micro/nanoscale systems.
- Understanding its behavior in real materials under realistic conditions (temperature, finite conductivity) is essential.
Purpose of the Study:
- To analyze the combined influence of nonzero temperature and finite conductivity on the Casimir force.
- To investigate this effect for two distinct geometries: parallel plates and a sphere above a plate.
Main Methods:
- Development of a perturbation theory based on two key parameters: relative temperature and relative penetration depth.
- Numerical computations to validate the perturbative results.
Main Results:
- The study quantifies the impact of temperature and conductivity on Casimir force calculations.
- Perturbative results show good agreement with direct computations for the considered systems.
Conclusions:
- The developed perturbation theory provides an accurate method for calculating temperature-dependent Casimir forces in real metals.
- Highlights potential inaccuracies in previous computations using the Lifshitz formula for temperature effects.
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