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arXiv · 1307.3361

Efficient method for controlling the spatial coherence of a laser

Micha Nixon·Brandon Redding·Asher Friesem·Hui Cao·Nir Davidson
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Abstract

An efficient method to tune the spatial coherence of a degenerate laser over a broad range with minimum variation in the total output power is presented. It is based on varying the diameter of a spatial filter inside the laser cavity. The number of lasing modes supported by the degenerate laser can be controlled from 1 to 320,000, with less than a 50% change in the total output power. We show that a degenerate laser designed for low spatial coherence can be used as an illumination source for speckle-free microscopy that is 9 orders of magnitude brighter than conventional thermal light.

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Micha Nixon, Brandon Redding, Asher Friesem, Hui Cao, Nir Davidson. 2013-07-12. Efficient method for controlling the spatial coherence of a laser. https://doi.org/10.1364/ol.38.003858

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