Title: Transverse mode analysis for free-space laser beams using Bayesian analysis

Abstract

Reliable and rapid assessment of the transverse mode quality of a free-space laser beam has a wide range of applications in laser development, research, and utilization. It has become even more important with recent advances in developing orbital angular momentum photon beams across a broad spectral region. In this work, a general modal analysis method for a free-space multimode laser beam has been developed based on Bayesian analysis. After transforming mode decomposition into a linear system problem, a Gaussian probabilistic model is used to find a closed-form solution. The method is found to be robust with the presence of Gaussian noise. Prior knowledge about the mode content can be incorporated into the method to improve the solution for situations when coherent disturbances or contamination are present in the laser beam. This method can be used to analyze the mode content for laser beams in different bases, such as Hermite–Gaussian (HG) modes and Laguerre–Gaussian (LG) modes. Three applications of this method are presented: a detailed modal analysis of the beam image from the incoherent intensity addition of HG modes and two examples of mode decomposition using the complex wavefront from the coherent superposition of HG and LG modes. The feasibility ofmore » this method is demonstrated using various simulation results. Based on digital images of a laser beam recorded without complex wavelength-limiting optics, in principle, this method can be used in a wide wavelength range from infrared to ultraviolet, and possibly x ray.« less

Authors:

Liu, Peifan ;

• Search DOE PAGES for author "Liu, Peifan"
• Search DOE PAGES for ORCID "0000-0002-7381-6153"

Yan, Jun ;

• Search DOE PAGES for author "Yan, Jun"
• Search DOE PAGES for ORCID "0000-0002-7378-3611"

Li, Wei; Wu, Ying K.

• Search DOE PAGES for author "Wu, Ying K."
• Search DOE PAGES for ORCID "0000-0001-8129-0561"

Publication Date:

Tue Apr 13 00:00:00 EDT 2021

Sponsoring Org.:

USDOE

OSTI Identifier:

1776475

Grant/Contract Number:  

FG02-97ER41033

Resource Type:

Publisher's Accepted Manuscript

Journal Name:

Applied Optics

Additional Journal Information:

Journal Name: Applied Optics Journal Volume: 60 Journal Issue: 12; Journal ID: ISSN 1559-128X

Publisher:

Optical Society of America

Country of Publication:

United States

Language:

English