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arXiv · 1806.05723

Precise amplitude, trajectory, and beam-width control of accelerating and abruptly autofocusing beams

Abstract

We show that it is possible to independently control both the trajectory and the maximum amplitude along the trajectory of a paraxial accelerating beam. This is accomplished by carefully engineering both the amplitude and the phase of the beam on the input plane. Furthermore, we show that the width of an accelerating beam is related only on the curvature of the trajectory. Therefore, we are able to produce beams with predefined beam widths and amplitudes. These results are useful in applications where precise beam control is important. In addition we consider radially symmetric abruptly autofocusing beams. We identify the important parameters that affect the focal characteristics. Consequently, we can design autofocusing beams with optimized parameters (such as sharper focus and higher intensity contrast). In all our calculations the resulting formulas are presented in an elegant and practical form in direct connection with the geometric properties of the trajectory. Finally we discuss methods that can be utilized to experimentally realize such optical waves.

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Michael Goutsoulas, Nikolaos K. Efremidis. 2018-06-14. Precise amplitude, trajectory, and beam-width control of accelerating and abruptly autofocusing beams. https://doi.org/10.1103/physreva.97.063831

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