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DOE OSTI · 23141983

Optomechanical interaction in fibre lasers with micro-optomechanical resonance structures

Egorov, F. A.
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Abstract

We report the results of studies of fibre lasers with passive modulators based on light-excited micro-optomechanical resonance structures (micro-oscillators). It is shown that in fibre lasers based on active fibres doped with rare-earth elements (Er, Er/Yb, Yb, Nd), the optomechanical interaction of laser radiation with micro-oscillators of various types (fibre-optic, microvolume) leads to self-oscillations of the characteristics of laser radiation at frequencies of relaxation oscillations and intermode beats synchronised with the frequencies of elastic eigenoscillations of micro-oscillators. It is found that in an ultra-long erbium – ytterbium fibre laser with a nonlinear mirror based on a microcantilever, laser photothermal excitation of the second mode of elastic transverse oscillations of the microcantilever makes it possible to perform passive mode locking exclusively due to Q-switching of the laser cavity. Pulsed lasing with a controlled repetition rate (∼76 kHz), a pulse duration of 2 – 5 μs and an output energy of 0.1 μJ per pulse is implemented. Based on a simplified physical model of the indicated fibre lasers with micro-oscillators, we have developed an approximate mathematical model describing the regimes of passive mode locking of fibre lasers with micro-oscillators that play the role of mirrors with a nonlinear reflection coefficient in the laser cavity. The prospects for the development and application of the considered laser systems are discussed. (control of laser radiation parameters)

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYAPPROXIMATIONSDOPED MATERIALSERBIUMEXCITATIONFIBERSINTERACTIONSKHZ RANGELASER CAVITIESLASER RADIATIONLASERSMODE LOCKINGOSCILLATIONSOSCILLATORSPULSESQ-SWITCHINGREFLECTIONRELAXATIONRESONANCEVISIBLE RADIATIONYTTERBIUM

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BibTeXRIS

Egorov, F. A.. 2020-08-01. Optomechanical interaction in fibre lasers with micro-optomechanical resonance structures. https://doi.org/10.1070/qel17116

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