arXiv subjects

Roman A. Baskov

Publications and source records attributed to Roman A. Baskov.

2 recordsLinked to original sources

arXiv2018

Laser-beam scintillations for weak and moderate turbulence

The scintillation index is obtained for the practically important range of weak and moderate atmospheric turbulence. To study this challenging range, the Boltzman-Langevin kinetic equation, describing light propagation, is derived from first principles of quantum optics based on the technique of the photon distribution function (PDF) [G. P. Berman et al., Phys. Rev. A 74, 013805 (2006)]. The paraxial approximation for laser beams reduces the collision integral for the PDF to a two-dimensional operator in the momentum space. Analytical solutions for the average value of PDF as well as for its fluctuating constituent are obtained using an iterative procedure. The calculated scintillation index is considerably greater than that obtained within the Rytov approximation even at moderate turbulence strength. The relevant explanation is proposed.

quant-ph↗

arXiv2015

Correlations of photon trajectories in the problem of light scintillations

A distribution function approach is applied to describe the dynamics of the laser beam in the Earth atmosphere. Using a formal solution of the kinetic equation for the distribution function, we have developed an iterative scheme for calculation of the scintillation index ($σ^2$). The problem reduces to obtaining the photon trajectories and their correlations. Bringing together theoretical calculations and many-fold computer integrations, the value of $σ^2$ is obtained. It is shown that a considerable growth of $σ^2$ in the range of a moderate turbulence is due to the correlations of different trajectories. The criteria of applicability of our approach for both the coherent and partially coherent light are derived.

quant-ph↗