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Velocities of transmission eigenchannels and diffusion.
Azriel Z Genack1,2, Yiming Huang3,4,5, Asher Maor3,4,6
1Department of Physics, Queens College of the City University of New York, Flushing, NY, 11367, USA. agenack@qc.cuny.edu.
Nature Communications
|March 24, 2024
Summary
Wave propagation in disordered media is not random. Distinct transmission eigenchannels maintain unique velocities, influencing wave dynamics and scattering parameters, challenging long-held assumptions in wave diffusion.
Area of Science:
- Wave physics
- Condensed matter physics
- Statistical mechanics
Background:
- Diffusion models predict wave randomization in disordered media.
- Transmission eigenchannels can enhance or suppress wave flux.
- Wave velocity is often assumed to be randomized in scattering media.
Purpose of the Study:
- To investigate the velocity statistics of transmission eigenchannels in disordered media.
- To determine if wave velocity is truly randomized or retains distinct characteristics.
- To explore the relationship between eigenchannel velocities and wave propagation dynamics.
Main Methods:
- Microwave measurements on disordered samples.
- Numerical simulations of wave propagation.
- Analysis of transmission eigenchannel properties.
Main Results:
- Wave velocities of different transmission eigenchannels are distinct and scale-invariant.
- Eigenchannel velocities are identical at incident and output surfaces.
- Diffusion coefficient and scattering parameters oscillate with sample width.
Conclusions:
- Wave velocity in scattering media is not irretrievably randomized.
- Transmission eigenchannels possess unique, persistent velocity statistics.
- Eigenchannel properties dictate energy density, diffusion, and propagation dynamics.
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