Recovering Quantum Information in Orbital Angular Momentum of Photons by Adaptive Optics

TL;DR

This paper investigates how adaptive optics can mitigate atmospheric turbulence effects on the orbital angular momentum of photons, enhancing quantum information transmission by correcting phase distortions modeled with Zernike functions.

Contribution

It provides a closed-form solution for residual errors after adaptive optics correction of orbital angular momentum states in turbulent atmospheres with Kolmogorov spectrum.

Findings

Residual errors decrease with more Zernike modes corrected

Higher orbital angular momentum states are more affected by turbulence

Adaptive optics improves quantum information fidelity

Abstract

Orbital angular momentum of photons is an intriguing system for the storage and transmission of quantum information, but it is rapidly degraded by atmospheric turbulence. We explore the ability of adaptive optics to compensate for this disturbance by measuring and correcting cumulative phase shifts in the wavefront. These shifts can be represented as a sum of Zernike functions; we analyze the residual errors after correcting up to a certain number of Zernike modes when an orbital angular momentum state is transmitted through a turbulent atmosphere whose density fluctuations have a Kolmogorov spectrum. We approximate the superoperator map that represents these residual errors and find the solution in closed form. We illustrate with numerical examples how this perturbation depends on the the number of Zernike modes corrected and the orbital angular momentum state of the light.