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Stochastic Dynamics of Incoherent Branched Flows
Josselin Garnier1, Antonio Picozzi2, Theo Torres2
1CMAP, CNRS, Ecole polytechnique, Institut Polytechnique de Paris, 91120 Palaiseau, France.
Physical Review Letters
|June 23, 2025
Summary
This study presents a new theory for branched flow, a wave phenomenon in disordered media. The research explains how coherence and interference influence wave propagation, impacting phenomena like freak waves.
Area of Science:
- Wave physics
- Disordered media
- Nonlinear optics
Background:
- Branched flow is a universal phenomenon observed in weakly disordered linear media.
- Previous studies primarily focused on coherent waves.
- Recent experiments observed optical branched flow using incoherent light, highlighting the role of phase-sensitive effects.
Purpose of the Study:
- To elaborate a stochastic theory for both coherent and incoherent branched flow.
- To derive closed-form equations for the intensity correlation function and scintillation index.
- To provide a framework for understanding branched flow in nonlinear media and its relation to freak waves.
Main Methods:
- Utilized the paraxial wave equation as a generic model.
- Developed a stochastic theory for coherent and incoherent branched flow.
- Performed accurate numerical simulations for validation.
Main Results:
- Derived closed-form equations governing the dynamics of incoherent branched flow.
- Quantitatively matched theoretical predictions with numerical simulations without free parameters.
- Demonstrated the significant impact of coherence and interference on branched flow.
Conclusions:
- The developed theory accurately describes coherent and incoherent branched flow.
- Coherence and interference are crucial factors in the formation of branched flow.
- The framework can be extended to study nonlinear media and phenomena like freak waves.
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