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The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
Published on: August 12, 2013
Phase anomalies in Bessel-Gauss beams
Myun-Sik Kim1, Toralf Scharf, Alberto da Costa Assafrao
1Optics & Photonics Technology Laboratory, Ecole Polytechnique Fédérale de Lausanne (EPFL), Neuchâtel, CH- 2000, Switzerland. myunsik.kim@epfl.ch
Optics Express
|December 25, 2012
Summary
Bessel-Gauss beams exhibit a unique phase anomaly in non-diverging regions, directly measured for the first time using longitudinal-differential interferometry. This finding offers new insights into the behavior of non-diffracting beams.
Area of Science:
- Optics and Photonics
- Laser Physics
- Wave Phenomena
Background:
- Bessel-Gauss beams are a class of non-diffracting beams.
- These beams are generated by focusing annularly shaped collimated laser beams.
- Understanding their phase evolution is crucial for applications utilizing non-diffracting light.
Purpose of the Study:
- To report the first direct measurement of the phase evolution of Bessel-Gauss beams.
- To investigate the phase anomaly in the non-diverging spatial domain of these beams.
- To provide a comprehensive analytical and numerical understanding of the observed phenomena.
Main Methods:
- Longitudinal-differential interferometry was employed for direct phase measurement.
- Experimental results were compared with numerical simulations.
- An analytical treatment was developed to explain the observed phase behavior.
Main Results:
- A continuously increasing phase anomaly was observed in the spatial domain where Bessel-Gauss beams do not diverge.
- The measured phase advance in this region is greater than that of a referential plane wave.
- Simulations and analytical models showed excellent agreement with experimental data.
Conclusions:
- The study successfully measured and explained the phase evolution of Bessel-Gauss beams.
- The findings confirm a unique phase anomaly in the non-diverging region of these beams.
- The results provide an intuitive explanation and validate theoretical models for Bessel-Gauss beam propagation.
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