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arXiv · 1608.06303

Explaining the mechanism of random lasing based sensing

Michele Gaio·Soraya Caixeiro·Benedetto Marelli·Fiorenzo Omenetto·Riccardo Sapienza
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Abstract

Here we report a random lasing based sensor which shows pH sensitivity exceeding by 2-orders of magnitude that of a conventional fluorescence sensor. We explain the sensing mechanism as related to gain modifications and lasing threshold nonlinearities. A dispersive diffusive lasing theory matches well the experimental results, and allow us to predict the optimal sensing conditions and a maximal sensitivity as large as 200 times that of an identical fluorescence-based sensor. The simplicity of operation and high sensitivity make it promising for future biosensing applications.

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Michele Gaio, Soraya Caixeiro, Benedetto Marelli, Fiorenzo Omenetto, Riccardo Sapienza. 2016-08-22. Explaining the mechanism of random lasing based sensing. https://doi.org/10.1103/physrevapplied.7.034005

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