Year: 2025
Type: article
Abstract: Optical beams with certain asymmetric profiles, such as the Airy beam, can depart from rectilinear propagation and instead travel along curved (typically parabolic) trajectories. Here we show that sculpting the spatiotemporal spectrum of optical pulses yields self-accelerating beams that have symmetric profiles, remain diffraction-free, and travel along power-law curves with propagation distance having arbitrary positive exponent (integer or fractional). We build upon propagation-invariant space-time wave packets (STWPs), in which each spatial frequency is associated with a single wavelength. A linear tilt in the propagation path of an STWP is produced by a corresponding tilt in the spectral domain. A curved trajectory is then produced through locally changing the tilt direction along the propagation axis, which requires associating a prescribed finite-bandwidth spatial spectrum to each wavelength. Using this approach, we realize symmetric STWPs traveling along curved trajectories that follow linear, quadratic, cubic, or even square-root power laws with an acceleration rate that is independent of the beam spatial scale. These novel, to the best of our knowledge, bending STWPs open new avenues for realizing target-avoidance with electromagnetic waves.
Source: Optics Letters
DOI: 10.1364/ol.571482
Authors: Layton A. Hall, Ayman F. Abouraddy
Institutions: University of Central Florida, Los Alamos National Laboratory
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Funder: Office of Naval Research
OpenAlex ID: W4413217592