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Nonequilibrium Casimir Force with a Nonzero Chemical Potential for Photons
Kaifeng Chen1,2, Shanhui Fan2
1Department of Applied Physics, Stanford University, California 94305, USA.
Physical Review Letters
|January 7, 2017
Summary
We introduce novel nonequilibrium Casimir forces using photon chemical potential. Modest voltages on semiconductors can create nanoscale repulsive forces, advancing solid-state system applications.
Area of Science:
- Condensed matter physics
- Quantum electrodynamics
- Nanotechnology
Background:
- Casimir forces arise from quantum vacuum fluctuations.
- Equilibrium Casimir forces are typically attractive.
- Controlling Casimir forces in solid-state systems is challenging.
Purpose of the Study:
- To introduce and investigate a new class of nonequilibrium Casimir forces.
- To explore the possibility of achieving repulsive Casimir forces in solid-state systems.
- To demonstrate the influence of photon chemical potential on Casimir forces.
Main Methods:
- Theoretical modeling of Casimir forces with nonzero photon chemical potential.
- Exact numerical calculations for a sphere-plate configuration.
- Analysis of forces in semiconductor systems subjected to external voltage.
Main Results:
- Non-equilibrium Casimir forces can dominate over equilibrium forces.
- Repulsive Casimir forces are achievable at the nanoscale with modest applied voltages.
- The effect is significant even for nanoscale sphere-plate separations.
Conclusions:
- Non-equilibrium Casimir forces offer a new pathway for controlling forces in solid-state systems.
- External voltage provides a tunable mechanism to achieve repulsion.
- This research advances the observation and application of Casimir forces in nanotechnology.
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