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arXiv · 2004.13923

Overcoming optical contrast limit of mesoscale light focusing by means of retrograde-reflection photonic nanojet

Yury E. Geints·Alexander A. Zemlyanov·Igor V. Minin·Oleg V. Minin
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Abstract

The physical origin of subwavelength photonic nanojet in retrograde-reflection mode (retro-PNJ) is theoretically considered. This specific type of photonic nanojet emerges upon sequential double focusing of a plane optical wave by a transparent dielectric microparticle located near a flat reflecting mirror. For the first time to the best of our knowledge, we report a unique property of retro-PNJ for increasing its focal length and intensity using microparticles with the optical contrast exceeding limiting value (n > 2) that fundamentally distinguishes retro-PNJ from regular PNJ behavior. This may drastically increase the trapping potential of PNJ-based optical tweezers.

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Yury E. Geints, Alexander A. Zemlyanov, Igor V. Minin, Oleg V. Minin. 2020-04-29. Overcoming optical contrast limit of mesoscale light focusing by means of retrograde-reflection photonic nanojet. https://doi.org/10.1364/ol.398367

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