New Methods for Retrieving Coherence Properties of Complex Optical Fields from Intensity Measurements
Researchers have developed new algorithms based on the Gerchberg-Saxton framework to reconstruct the spatial coherence properties of partially coherent light from near- and far-field intensity measurements. The approach includes a Tensor GS algorithm for high accuracy and a Monte Carlo variant for reduced computational cost, validated on simulated arrays up to 600 beams and experimentally on a 130-laser array. This advancement enables better characterization of coherence in optical systems relevant to high-power lasers and quantum applications.
A new paradigm for coherence retrieval has been presented that reconstructs the first-order spatial coherence function (mutual intensity) of partially coherent light from intensity measurements taken in both near and far fields. The method introduces two complementary approaches: a four-dimensional Tensor GS algorithm that directly reconstructs mutual intensity with high accuracy, and a Monte Carlo GS variant that reduces computational demands through controlled approximation. Validation was performed on simulated linear and ring arrays containing up to 600 beams with prescribed Gaussian decaying coherence patterns. Experimental application of the Tensor GS method to a triangular array of 130 coupled lasers with inhomogeneous spatial coherence demonstrated good agreement with theoretical predictions, achieving root mean square phase errors as low as 2π/250. These methods address a fundamental need in characterizing coherence properties of complex optical fields for applications ranging from high-power laser arrays to quantum coherent systems.
What's missing
The study does not discuss potential limitations of the methods when applied to optical fields with non-Gaussian coherence decay patterns, nor does it address computational scaling challenges for arrays significantly larger than 600 beams. The paper also does not compare performance against alternative coherence retrieval methods that may exist in the literature.
What different sources said
- arXiv physicsCenter
Phase and coherence retrieval from near- and far-field intensities
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