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Updated: May 22, 2026
10:03
The Preparation of Electrohydrodynamic Bridges from Polar Dielectric Liquids
Published on: September 30, 2014
Drag in a resonantly driven polariton fluid
A C Berceanu1, E Cancellieri, F M Marchetti
1Departamento de Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid, E-28049 Madrid, Spain. andrei.berceanu@uam.es
Summary
We analytically calculated the drag force on a defect in a polariton fluid. The critical velocity for drag depends on excitation conditions, exceeding sound speed for gapped spectra.
Area of Science:
- Quantum optics
- Condensed matter physics
- Mesoscopic physics
Background:
- Polariton fluids exhibit unique quantum phenomena.
- Interaction-renormalised pump detuning classifies excitation spectra.
- Defects in fluids can induce drag forces.
Purpose of the Study:
- To analytically evaluate the drag force on a point-like defect in a coherently driven polariton fluid.
- To investigate the influence of excitation spectra on drag force and critical velocity.
- To determine the dependence of drag force on polariton lifetime.
Main Methods:
- Linear response theory applied to a polariton fluid.
- Analytical evaluation of drag force in the pump-only configuration.
- Analysis of collective excitation spectra based on pump detuning.
Main Results:
- Drag force crossover from subsonic to supersonic regimes observed for zero and positive detuning.
- Critical velocity equals sound speed for linear and diffusive-like spectra.
- Critical velocity exceeds sound speed for gapped spectra.
- Subcritical drag force depends solely on polariton lifetime.
Conclusions:
- The drag force characteristics are sensitive to the polariton fluid's excitation spectrum.
- Polariton lifetime linearly influences subcritical drag force.
- Analytical results align with previous numerical findings for finite-size defects.
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