Effect of aberrations on the beam quality factor of Hermite-Gauss beams.

The effect of aberrations on the beam quality factor (M) of Hermite-Gauss (HG) beams is examined. Using the method of moments, we derive closed-form analytical expressions of M due to astigmatism and spherical aberration. Our analysis reveals that the radius of the HG beams plays a significant role in determining the effect of the aberrations on M.

Beam quality factor of aberrated Laguerre-Gaussian optical beams.

The influence of aberrations on the beam quality factor of Laguerre-Gaussian beams is investigated. We derive analytical expressions for the beam quality factor due to astigmatism and spherical aberration. We show that the width of a Laguerre-Gaussian beam is a significant parameter that determines the aberration effects on the beam quality factor.

2020 JOSA A Emerging Researcher Best Paper Prize: editorial.

JOSA A Editor-in-Chief P. Scott Carney, Feature Editor Johannes Courtial, and members of the 2020 Emerging Researcher Best Paper Prize Committee announce the recipient of the 2020 prize for the best paper published by an emerging researcher in the Journal.

Free-space optical communication link with shape-invariant orbital angular momentum Bessel beams.

We present an alternative orbital angular momentum (OAM) solution for free-space optical communications in the form of shape-invariant Bessel beams. We use a generalized approach for generating these long-range self-healing beams with a phase-only element encoded on a spatial light modulator and imbue them with OAM. We study the performance of helical OAM beams as well as these long-range Bessel-like OAM beams over a real-world outdoor optical link of 150 m and show comparable performance.

Are Bessel beams resilient to aberrations and turbulence?

It is understood from the conical wave picture that Bessel beams may self-heal after certain opaque obstructions, but the extrapolation to transparent phase screens is not self-evident. Here we consider the propagation of Bessel beams through aberrated obstacles and show that the self-healing is not guaranteed, but rather a function of the severity of the aberration. Paradoxically, we explain why strong aberrations may show self-healing while weak aberrations will not, and highlight the parameters that influence this.

Comparing mode-crosstalk and mode-dependent loss of laterally displaced orbital angular momentum and Hermite-Gaussian modes for free-space optical communication.

There is interest in using orbital angular momentum (OAM) modes to increase the data speed of free-space optical communication. A prevalent challenge is the mitigation of mode-crosstalk and mode-dependent loss that is caused by the modes' lateral displacement at the data receiver. Here, the mode-crosstalk and mode-dependent loss of laterally displaced OAM modes (LG, LG) are experimentally compared to that of a Hermite-Gaussian (HG) mode subset (HG, HG).