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

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, the authors report on Bloch oscillations of hybrid light-matter particles, called exciton-polaritons (polaritons), being confined in an array of coupled microcavity waveguides. To this end, the waveguide widths and their mutual couplings are carefully designed such that a constant energy gradient is induced perpendicular to the direction of motion of the propagating polaritons. This technique allows us to directly observe and study Bloch oscillations in real- and momentum-space. Furthermore, the experimental findings are supported by numerical simulations based on a modified Gross-Pitaevskii approach. This work provides an important transfer of basic concepts of quantum mechanics to integrated solid state devices, using quantum fluids of light.

Automated summary

This study reports on the Bloch oscillations of exciton-polaritons in an array of coupled microcavity waveguides, achieved by carefully designing the waveguide widths and mutual couplings to induce a constant energy gradient perpendicular to the direction of motion. This technique allows for direct observation and study of Bloch oscillations in real- and momentum-space, supported by numerical simulations based on a modified Gross-Pitaevskii approach. It represents an important application of quantum mechanics concepts to integrated solid state devices using quantum fluids of light.