Bloch Oscillations of Hybrid Light-Matter Particles in a Waveguide Array

TL;DR

This paper demonstrates the observation of Bloch oscillations in exciton-polaritons within microcavity waveguide arrays, bridging quantum mechanical phenomena with integrated solid-state photonic devices.

Contribution

It introduces a method to induce and observe Bloch oscillations of hybrid light-matter particles in engineered waveguide arrays, supported by numerical simulations.

Findings

Direct observation of Bloch oscillations in exciton-polaritons

Controlled energy gradient in waveguides enables oscillation studies

Numerical simulations confirm experimental results

Abstract

Bloch oscillations are a phenomenon well known from quantum mechanics where electrons in a lattice experience an oscillatory motion in the presence of an electric field gradient. Here, we report on Bloch oscillations of hybrid light-matter particles, called exciton-polaritons, being confined in an array of coupled microcavity waveguides. To this end, we carefully design the waveguides, widths and their mutual couplings such that a constant energy gradient is induced perpendicular to the direction of motion of the propagating exciton-polaritons. This technique allows us to directly observe and study Bloch oscillations in real- and momentum-space. Furthermore, we support our experimental findings by numerical simulations based on a modified Gross-Pitaevskii approach. Our work provides an important transfer of basic concepts of quantum mechanics to integrated solid state devices, using quantum fluids of light.