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arXiv · 1311.5788

An improved beam waist formula for ultrashort, tightly-focused linearly, radially, and azimuthally polarized laser pulses in free space

Liang Jie Wong·Franz X. Kärtner·Steven G. Johnson
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Abstract

We derive an asymptotically accurate formula for the beam waist of ultrashort, tightly-focused fundamental linearly-polarized, radially-polarized, and azimuthally-polarized modes in free space. We compute the exact beam waist via numerical cubature to ascertain the accuracy with which our formula approximates the exact beam waist over a broad range of parameters of practical interest. Based on this, we describe a method of choosing parameters in the model given the beam waist and pulse duration of a laser pulse.

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Liang Jie Wong, Franz X. Kärtner, Steven G. Johnson. 2014-02-25. An improved beam waist formula for ultrashort, tightly-focused linearly, radially, and azimuthally polarized laser pulses in free space. https://doi.org/10.1364/ol.39.001258

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