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arXiv · 2105.01743

Super-resolution linear optical imaging in the far field

A. A. Pushkina·G. Maltese·J. I. Costa-Filho·P. Patel·A. I. Lvovsky
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Abstract

The resolution of optical imaging devices is ultimately limited by the diffraction of light. To circumvent this limit, modern super-resolution microscopy techniques employ active interaction with the object by exploiting its optical nonlinearities, nonclassical properties of the illumination beam, or near-field probing. Thus, they are not applicable whenever such interaction is not possible, for example, in astronomy or non-invasive biological imaging. Far-field, linear-optical super-resolution techniques based on passive analysis of light coming from the object would cover these gaps. In this paper, we present the first proof-of-principle demonstration of such a technique. It works by accessing information about spatial correlations of the image optical field and, hence, about the object itself via measuring projections onto Hermite-Gaussian transverse spatial modes. With a basis of 21 spatial modes in both transverse dimensions, we perform two-dimensional imaging with twofold resolution enhancement beyond the diffraction limit.

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A. A. Pushkina, G. Maltese, J. I. Costa-Filho, P. Patel, A. I. Lvovsky. 2021-04-30. Super-resolution linear optical imaging in the far field. https://doi.org/10.1103/physrevlett.127.253602

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