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Beaming random lasers with soliton control.

ABSTRACT: Random lasers are resonator-less light sources where feedback stems from recurrent scattering at the expense of spatial profile and directionality. Suitably-doped nematic liquid crystals can random lase when optically pumped near resonance(s); moreover, through molecular reorientation within the transparency region, they support self-guided optical spatial solitons, i.e., light-induced waveguides. Here, we synergistically combine solitons and collinear pumping in weakly scattering dye-doped nematic liquid crystals, whereby random lasing and self-confinement concur to beaming the emission, with several improved features: all-optical switching driven by a low-power input, laser directionality and smooth output profile with high-conversion efficiency, externally controlled angular steering. Such effects make soliton-assisted random lasers an outstanding route towards application-oriented random lasers.

SUBMITTER: Perumbilavil S

PROVIDER: S-EPMC6155064 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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Beaming random lasers with soliton control.

Perumbilavil Sreekanth S Piccardi Armando A Barboza Raouf R Buchnev Oleksandr O Kauranen Martti M Strangi Giuseppe G Assanto Gaetano G

Nature communications 20180921 1

Random lasers are resonator-less light sources where feedback stems from recurrent scattering at the expense of spatial profile and directionality. Suitably-doped nematic liquid crystals can random lase when optically pumped near resonance(s); moreover, through molecular reorientation within the transparency region, they support self-guided optical spatial solitons, i.e., light-induced waveguides. Here, we synergistically combine solitons and collinear pumping in weakly scattering dye-doped nema ...[more]

PMID: 30242163

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