An Archimedes' Screw for Light

Abstract

An Archimedes' Screw captures water, feeding energy into it by lifting it to a higher level. We introduce the first instance of an optical Archimedes' Screw, and demonstrate how this system is capable of capturing light, dragging it and amplifying it. We unveil new exact analytic solutions to Maxwell's Equations for a wide family of chiral space-time media, and show their potential to achieve chirally selective amplification within widely tunable parity-time-broken phases. Our work, which may be readily implemented via pump-probe experiments with circularly polarized beams, opens a new direction in the physics of time-varying media by merging the rising field of spacetime metamaterials and that of chiral systems, and may form a new playground for topology and non-Hermitian physics, with potential applications to chiral spectroscopy and sensing.

Photonics of time-varying media

“…189 Chiral versions of synthetically moving and amplifying electromagnetic media, mimicking the Archimedean screw for fluids, have recently been proposed, and may be realized with circularly polarized pump-probe experiments. 190 Topology also occupies a prime seat, with Floquet topological insulators having been realized in acoustics, 191 and theoretically proposed for light. 192 Further related opportunities have been demonstrated for photonic realizations of the Aharonov-Bohm effect, 193 as well as for the engineering of Weyl points (three-dimensional spectral degeneracies analogous to Dirac points, signatures of topological states) within spatially 2D systems, exploiting a synthetic frequency dimension.…”

Floquet metamaterials

“…The framework of metamaterials indeed offers a rich host of opportunities for implementations and further explorations of Floquet engineering. Their subwavelength constitutive elements, the meta-atoms, support engineered scattering features ideally suited to support the exotic targeted response, playing a paramount role in defining emergent responses, such as dispersive [51], chiral [52], non-Hermitian [53] and nonreciprocal properties [11,54]. In the next section we argue that, in analogy with spatial metamaterials, the form of temporal switching imposed on a medium can be treated as a temporal meta-atom, offering a wealth of new opportunities for engineering wave phenomena.…”

Photonics of Time-Varying Media

“…181 Chiral versions of synthetically moving and amplifying electromagnetic media, mimicking the Archimedean screw for fluids, have recently been proposed, and may be realized with circularly polarized pump-probe experiments. 182 Topology also occupies a prime seat, with Floquet topological insulators having been realized in acoustics, 183 and theoretically proposed for light. 184 Further related opportunities have been demonstrated for photonic realizations of the Aharonov-Bohm effect, 185 as well as higher dimensional topological effects such as Weyl points (topological invariants for 3D structures) in spatially 2D systems, realized by exploiting a synthetic frequency dimension.…”