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Related Experiment Video

Updated: Jul 7, 2026

Theoretical Calculation and Experimental Verification for Dislocation Reduction in Germanium Epitaxial Layers with Semicylindrical Voids on Silicon
06:57

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Published on: July 17, 2020

Density of turbulence-induced phase dislocations.

V V Voitsekhovich, D Kouznetsov, D K Morozov

    Applied Optics
    |February 21, 2008
    PubMed
    Summary

    Light-wave propagation through turbulent media creates phase dislocations, which are zones of multi-valued phase. This study estimates dislocation density under various conditions, yielding an empirical formula useful for atmospheric and adaptive optics.

    Area of Science:

    • Optics
    • Wave propagation
    • Fluid dynamics

    Background:

    • Light-wave propagation through turbulent media can cause phase dislocations.
    • Phase dislocations are characterized by zones where the wave's phase is a multi-valued function of spatial coordinates.
    • Understanding these dislocations is crucial for applications like atmospheric and adaptive optics.

    Purpose of the Study:

    • To investigate and estimate the density of turbulence-induced phase dislocations.
    • To analyze the influence of various turbulence conditions, wavelength, and inner scales on dislocation density.
    • To derive an empirical formula for dislocation density applicable across a wide range of conditions.

    Main Methods:

    • Theoretical treatment of phase dislocations.

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  • Numerical simulations using the parabolic equation approximation.
  • Analysis of results under varying turbulence strengths, wavelengths, and inner scales.

    • Main Results:

    • Phase dislocations are a significant consequence of light propagation in turbulent media.
    • Dislocation density is dependent on turbulence strength, wavelength, and inner scale.
    • An empirical formula for dislocation density was successfully derived, covering diverse conditions.

    Conclusions:

    • The derived empirical formula provides a practical tool for predicting phase dislocation density.
    • The findings are relevant for improving performance in atmospheric and adaptive optics systems.
    • This research contributes to a better understanding of wave propagation phenomena in turbulent environments.