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arXiv · 2109.04009

Arbitrarily accelerating space-time wave packets

Layton A. Hall·Murat Yessenov·Ayman F. Abouraddy
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Abstract

All known realizations of optical wave packets that accelerate along their propagation axis, such as Airy wave packets in dispersive media or wave-front-modulated X-waves, exhibit a constant acceleration; that is, the group velocity varies linearly with propagation. Here we synthesize space-time wave packets that travel in free space with arbitrary axial acceleration profiles, including group velocities that change with integer or fractional exponents of the distance. Furthermore, we realize a composite acceleration profile: the wave packet first accelerates from an initial to a terminal group velocity, decelerates back to the initial value, and then travels at a fixed group velocity. These never-before-seen optical-acceleration phenomena are all produced using the same experimental arrangement that precisely sculpts the wave packet's spatio-temporal spectral structure.

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Layton A. Hall, Murat Yessenov, Ayman F. Abouraddy. 2021-09-09. Arbitrarily accelerating space-time wave packets. https://doi.org/10.1364/ol.442885

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