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arXiv · 2209.03309

Space-time wave packets propagating a kilometer in air

Layton A. Hall·Miguel A. Romer·Bryan L. Turo·Tina M. Hayward·Rajesh Menon·Ayman F. Abouraddy
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Abstract

We report on the diffraction-free propagation of space-time wave packets (STWPs) -- a class of propagation-invariant pulsed beams -- for $\sim\!1$ km in an open-air laser range in a low-turbulence scenario. Making use of $\approx\!100$-fs pulses (bandwidth $\sim\!25$ nm) at a wavelength of $\approx\!1$ $\mu$m, we construct an STWP with a transverse width of $\approx\!2$ mm that expands to $\approx\!3$ mm after $\sim\!500$ m, and another that expands from $\approx\!8$ mm to $\approx\!10$ mm after 1 km. The propagation of the STWPs is compared to Gaussian wave packets of the same transverse spatial width and bandwidth. We establish a theoretical model that accounts for the significant factors limiting the STWP propagation distance and suggests the path to further extending this distance.

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Layton A. Hall, Miguel A. Romer, Bryan L. Turo, Tina M. Hayward, Rajesh Menon, Ayman F. Abouraddy. 2022-09-07. Space-time wave packets propagating a kilometer in air. https://arxiv.org/abs/2209.03309

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