Probing microcavity polariton superfluidity through resonant Rayleigh scattering

Area of Science:

• Quantum fluid dynamics
• Condensed matter physics
• Non-equilibrium systems

Background:

• Polariton fluids in microcavities exhibit complex dynamics.
• Understanding non-equilibrium quantum phenomena is crucial.
• Resonant Rayleigh scattering is a probe for excitation spectra.

Purpose of the Study:

• Investigate the motion of a continuous-wave laser-injected polariton fluid.
• Analyze the impact of static defects on excitation spectra.
• Characterize the superfluid regime and its observable signatures.

Main Methods:

• Injection of a polariton fluid into a planar microcavity.
• Analysis of Bogoliubov-like excitations.
• Measurement of resonant Rayleigh scattering in momentum and real space.
• Tuning of excitation angle and frequency.

Main Results:

• Defects influence the shape and intensity of Rayleigh scattering patterns.
• A superfluid regime was identified, characterized by a collapsed scattering ring.
• Normalized intensity of Rayleigh scattering decreases in the superfluid regime.
• Observed collective excitation spectra without equilibrium analogs.

Conclusions:

• Rayleigh scattering is a sensitive probe for non-equilibrium polariton fluid dynamics.
• The superfluid regime exhibits distinct spectral properties.
• Tunability of excitation parameters allows observation of novel quantum phenomena.