Observation of photonic spin-momentum locking due to coupling of achiral metamaterials and quantum dots

TL;DR

This paper reports the experimental observation of photonic spin-momentum locking resulting from the coupling of achiral quantum dots with hyperbolic metamaterials, revealing new topological photonic modes detectable in the far field.

Contribution

It demonstrates the emergence of spin-momentum locking in achiral quantum dot and metamaterial systems, supported by theoretical modeling of photon Green's functions.

Findings

Directional and chiral emission observed from quantum dots

Photonic topological modes detected in the far field

Theoretical explanation based on photon Green's function provided

Abstract

Here, we report observations of photonic spin-momentum locking in the form of directional and chiral emission from achiral quantum dots (QDs) evanescently coupled to achiral hyperbolic metamaterials (HMM). Efficient coupling between QDs and the metamaterial leads to emergence of these photonic topological modes which can be detected in the far field. We provide theoretical explanation for the emergence of spin-momentum locking through rigorous modeling based on photon Green's function where pseudo spin of light arises from coupling of QDs to evanescent modes of HMM.