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arXiv · 1909.00666

Overcoming the speckle correlation limit to achieve a fiber wavemeter with attometer resolution

Graham D. Bruce·Laura O'Donnell·Mingzhou Chen·Kishan Dholakia
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Abstract

The measurement of the wavelength of light using speckle is a promising tool for the realization of compact and precise wavemeters and spectrometers. However, the resolution of these devices is limited by strong correlations between the speckle patterns produced by closely-spaced wavelengths. Here, we show how principal component analysis of speckle images provides a route to overcome this limit. Using this, we demonstrate a compact wavemeter which measures wavelength changes of a stabilized diode laser of 5.3 am, eight orders of magnitude below the speckle correlation limit.

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Graham D. Bruce, Laura O'Donnell, Mingzhou Chen, Kishan Dholakia. 2019-09-02. Overcoming the speckle correlation limit to achieve a fiber wavemeter with attometer resolution. https://doi.org/10.1364/ol.44.001367

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