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Numerical solution of Maxwell equations by a finite-difference time-domain method in a medium with frequency and
N N Potravkin1, I A Perezhogin, V A Makarov
1Faculty of Physics and International Laser Center of Lomonosov Moscow State University, Moscow, Russia.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|December 11, 2012
Summary
We present a new method for solving Maxwell equations in optical media with dispersion. This approach reveals novel light pulse propagation behaviors, including polarization changes not predicted by standard linear optical activity models.
Area of Science:
- Computational Electromagnetics
- Optics and Photonics
- Mathematical Physics
Background:
- Maxwell's equations govern electromagnetic phenomena.
- Finite-difference time-domain (FDTD) methods are common for solving these equations.
- Understanding light propagation in dispersive media is crucial for optical technologies.
Purpose of the Study:
- To introduce a generalized FDTD method for simulating light propagation.
- To investigate light pulse behavior in linear optical media with frequency and spatial dispersion.
- To explore deviations from conventional linear optical activity.
Main Methods:
- Generalization of the finite-difference time-domain method.
- Incorporation of auxiliary differential equations for dispersion.
- Application to short, plane-wave, linearly polarized light pulses.
Main Results:
- The proposed method accurately simulates light propagation in complex optical media.
- Observed propagation features differ significantly from established linear optical activity.
- Linearly polarized pulses can evolve into elliptically polarized pulses during propagation.
Conclusions:
- The developed method offers a powerful tool for studying light-matter interactions.
- New phenomena in light pulse propagation, such as self-induced polarization changes, are identified.
- These findings challenge existing models of linear optical activity.
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