Phase-factor spectra of turbulent phase screens

The optical phase$ϕ<#comment/>$is a key quantity in the physics of light propagating through a turbulent medium. In certain respects, however, the statistics of the phasefactor,$ψ<#comment/>=exp⁡<#comment/>(iϕ<#comment/>)$, are more relevant than the statistics of the phase itself. Here, we present a theoretical analysis of the 2D phase-factor spectrum$Fψ<#comment/>(κ<#comment/>)$of a random phase screen. We apply the theory to four types of phase screens, each characterized by a power-law phase structure function,$Dϕ<#comment/>(r)=(r/rc)γ<#comment/>$(where$rc$is the phase coherence length defined by$Dϕ<#comment/>(rc)=1rad2$), and a probability density function$pα<#comment/>(α<#comment/>)$of the phase increments for a given spatial lag. We analyze phase screens with turbulent ($γ<#comment/>=5/3$) and quadratic ($γ<#comment/>=2$) phase structure functions and with normally distributed (i.e., Gaussian) versus Laplacian phase increments. We find that there is a pronounced bump in each of the four phase-factor spectra$Fψ<#comment/>(κ<#comment/>)$. The precise location and shape of the bump are different for the four phase-screen types, but in each case it occurs at$κ<#comment/>∼<#comment/>1/rc$. The bump is unrelated to the well-known more »

Authors:
Publication Date:
NSF-PAR ID:
10288356
Journal Name:
Journal of the Optical Society of America A
Volume:
38
Issue:
9
Page Range or eLocation-ID:
Article No. 1339
ISSN:
1084-7529; JOAOD6
Publisher:
Optical Society of America
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