Exciting space-time surface plasmon polaritons by irradiating a nanoslit structure.

Space-time (ST) wave packets are propagation-invariant pulsed optical beams that travel freely in dielectrics at a tunable group velocity without diffraction or dispersion. Because ST wave packets maintain these characteristics even when only one transverse dimension is considered, they can realize surface-bound waves (e.g.

Theory of space-time supermodes in planar multimode waveguides.

When an optical pulse is focused into a multimode waveguide or fiber, the energy is divided among the available guided modes. Consequently, the initially localized intensity spreads transversely, the spatial profile undergoes rapid variations with axial propagation, and the pulse disperses temporally. Space-time (ST) supermodes are pulsed guided field configurations that propagate invariantly in multimode waveguides by assigning each mode to a prescribed wavelength.

Hybrid guided space-time optical modes in unpatterned films.

Light is confined transversely and delivered axially in a waveguide. However, waveguides are lossy static structures whose modal characteristics are fundamentally determined by their boundary conditions. Here we show that unpatterned planar waveguides can provide low-loss two-dimensional waveguiding by using space-time wave packets, which are unique one-dimensional propagation-invariant pulsed optical beams.

Efficient coupling of a quantum cascade laser to a few-mode chalcogenide fiber.

We report efficient coupling of a quantum cascade laser (QCL) into step-index chalcogenide fibers (As S ). Mechanically robust and low-loss chalcogenide fibers were fabricated using a hybrid, multi-material thermal drawing process. With suitable free-space optics, more than 160 mW of optical power was coupled into the fiber with predominantly single-mode excitation.

Efficient coupling of a quantum cascade laser to a few-mode chalcogenide fiber: erratum.

The authors wish to acknowledge an additional funding source which was absent from our manuscript.