2017

Spin-Momentum Locking in the Near Field of Metal Nanoparticles

Light carries both spin and momentum. Spin-orbit interactions (SOI) of light come into play at the subwavelength scale of nano-optics and nano-photonics, where they determine the behavior of light.

Here we investigate spin-orbit interactions in the near field of metal nanostructures supporting localized surface plasmons. These systems can confine light to very small dimensions below the diffraction limit, leading to a striking near-field enhancement.

We find that the spin of the incident light can control the rotation direction of the canonical momentum.

ACS Photonics 2017, 4, 9, 2242-2249

Biomineral Amorphous Lasers through Light-Scattering Surfaces Assembled by Electrospun Fiber Templates.

Here we show how biomineralization might enable the one-step generation of components for amorphous photonics, in which light is made to travel through disordered scattering systems, and particularly of active devices such as random lasers, by using electrospun fiber templates.

The resulting, complex optical material is characterized and modelled to elucidate scattered fields and lasing performance.

Tightly-controlled nanofabrication of direct biological inspiration establishes a new concept for the additive manufacturing of engineered light-diffusing materials and photonic components, not addressed by existing technologies.

Laser Photonics Rev. 2017, 170022

Coherent backscattering of Raman light

Coherent backscattering of light is observed when electromagnetic waves undergo multiple scattering within a disordered optical medium. So far, coherent backscattering of light has been studied extensively for elastic (or Rayleigh) light scattering. The occurrence of inelastic scattering affects the visibility of the backscattering effect by reducing the degree of optical coherence in the diffusion process.

Here, we discuss the first experimental observation of a constructive interference effect in the inelastically backscattered Raman radiation from strongly diffusing silicon nanowire random media.

The observed phenomenon originates from the coherent nature of the Raman scattering process, which typically occurs on a scale given by the phonon coherence length. We interpret our results in the context of a theoretical model of mixed Rayleigh–Raman random walks to shed light on the role of phase coherence in multiple scattering phenomena.

NATURE PHOTONICS | VOL 11 | MARCH 2017