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Updated: Jul 1, 2025
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Published on: December 3, 2013
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Goos-Hänchen shift for coupled vibrational modes in a semiconductor structure.
Diosdado Villegas1,2, Zorayda Lazcano2, Jesús Arriaga2
1Departamento de Física, Universidad Central 'Marta Abreu' de Las Villas, Santa Clara, Cuba.
Summary
This study theoretically investigates the Goös-Hanchen shift (GHS) in semiconductor thin films. Enhanced GHS values for acoustic and optical modes suggest potential applications in acoustic device design.
Area of Science:
- Acoustics and Optics
- Condensed Matter Physics
- Materials Science
Background:
- The Goös-Hanchen shift (GHS) describes the transverse displacement of a reflected or transmitted light beam.
- Understanding GHS in thin films is crucial for optical and acoustic device applications.
- Semiconductor thin films offer unique properties for manipulating vibrational modes.
Purpose of the Study:
- To theoretically investigate the Goös-Hanchen shift (GHS) for acoustic and optical vibrational modes.
- To analyze the impact of incident angle on GHS in a semiconductor thin film.
- To explore the coupling between longitudinal and transverse modes and its effect on GHS.
Main Methods:
- Theoretical analysis of acoustic and optical vibrational modes.
- Investigation of reflection and transmission from a semiconductor thin film.
- Examination of GHS under varying incident angles and mode frequencies.
Main Results:
- Acoustic GHS can be up to seven times the film thickness and 20 times the incident wavelength.
- Optical GHS can exceed 30 times the incident wavelength.
- Significant amplification of GHS is strongly influenced by incident angle and mode frequency.
Conclusions:
- The Goös-Hanchen shift is significantly amplified in semiconductor thin films.
- Observed GHS values highlight the potential for GHS in acoustical systems.
- This research opens possibilities for designing advanced acoustic devices.
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