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Negative Goos-Hänchen shift in periodic media
Mikael C Rechtsman1, Yaroslav V Kartashov, Frank Setzpfandt
1Department of Physics and Solid State Institute, Technion, Haifa, Israel.
Optics Letters
|November 18, 2011
Summary
A negative Goos-Hänchen shift, a backward displacement of light, can occur in periodic media like waveguide arrays under specific conditions. This phenomenon is crucial for understanding light behavior in structured optical materials.
Area of Science:
- Optics and Photonics
- Condensed Matter Physics
Background:
- The Goos-Hänchen effect describes the transverse shift of a totally internally reflected light beam.
- Periodic media, such as waveguide arrays, exhibit unique light propagation characteristics.
Purpose of the Study:
- To investigate the occurrence of a negative Goos-Hänchen shift in periodic media.
- To identify the conditions under which this phenomenon is observed.
Main Methods:
- Theoretical analysis of wave packet propagation.
- Numerical simulations of light reflection in periodic structures.
Main Results:
- Demonstrated the possibility of a negative Goos-Hänchen shift.
- Identified specific conditions in periodic media, like waveguide arrays, that lead to this backward displacement of a reflected wave packet.
Conclusions:
- The findings reveal novel light-matter interactions in periodic optical systems.
- This work has implications for designing advanced optical devices and understanding wave phenomena.
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