Space-time wave packets localized in all dimensions

Abstract

Optical wave packets that are localized in space and time, but nevertheless overcome diffraction and travel rigidly in free space, are a long sought-after field structure with applications ranging from microscopy and remote sensing, to nonlinear and quantum optics. However, synthesizing such wave packets requires introducing non-differentiable angular dispersion with high spectral precision in two transverse dimensions, a capability that has eluded optics to date. Here, we describe an experimental strategy capable of sculpting the spatio-temporal spectrum of a generic pulsed beam by introducing arbitrary radial chirp via two-dimensional conformal coordinate transformations of the spectrally resolved field. This procedure yields propagation-invariant `space-time' wave packets localized in all dimensions, with tunable group velocity in the range from $0.7c$ to $1.8c$ in free space, and endowed with prescribed orbital angular momentum. By providing unprecedented flexibility in sculpting the three-dimensional structure of pulsed optical fields, our experimental strategy promises to be a versatile platform for the emerging enterprise of space-time optics.

12 pages of Main text with 7 figures. 37 pages of Supplementary document with 18 figures

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Cited by in corpus (13)

• Roadmap on spatiotemporal light fields
• Nondiffracting Supertoroidal Pulses: Optical "Kármán vortex streets"
• Experimental observation of spontaneous emission of space-time wavepacket in a multimode optical fiber
• Observation of optical de Broglie-Mackinnon wave packets
• Observation of ultrabroadband striped space-time surface plasmon polaritons
• Rotated chirped volume Bragg gratings for compact spectral analysis
• Towards optical toroidal wavepacket through tightly focusing of cylindrical vector two dimensional spatiotemporal optical vortex
• Ultra-compact synthesis of space-time wave packets
• Relativistic transformations of quasi-monochromatic optical beams
• Coupling to multi-mode waveguides with space-time shaped free-space pulses
• Theory of space-time supermodes in planar multimode waveguides
• Electromagnetic Field Theory in Superluminal Spacetime
• Bending space-time wave packets