Self-organized coherence in fiber laser arrays

Abstract

Self-organized coherence between fiber lasers has been reported both via all-fiber 2x2 directional coupler trees and in spatially multi-core fibers. We have taken this a major step forward, coupling together a number of independent fiber lasers to obtain a spatially and spectrally coherent far field, with no active length, polarization, or amplitude control. The near field output comes from a spatial array rather than from a single fiber, making this approach scalable to extremely high power.

Coherent combining of fibre lasers

“…The unfilled aperture designation brings together methods that coherently combine an array of multiple identical laser beams [9][10][11]. Configuration for which laser beams are spatially separated in the near field and are superimposed in the far field is a common feature of this beam combining technique.…”

“…The fibered nature of the laser system makes evanescent coupling simple by drawing locally the N fibres closer like a fused star coupler that has been cleaved across the narrowest part. Lately, a tapered bundle of seven fibres was connected to seven Neodymium doped fibres (110 mW per laser) to experiment such evanescent wave coupling method [10]. There was no symmetry in the coupler that was made from a twisted bundle of fibres in random position.…”

Theoretical study on phase locking of the array of fiber lasers coupled by bi-dimensional mutual injection

“…Here, it should be noted that, even with the nonzero time duration, the output phase states are not totally irregular. Actually, because of phase locking of the array, only certain phase states (i.e., the phase-locked states) can be exported from the array (see (17)). It is found that an N-laser array can output 2 N −1 phase-locked states.…”

“…31 Later, it was utilized to build the fiber laser array. Prior to the interference array (where only one port is used for output and the burden capability of the unique output port limits the power scaling of the whole array), [17][18][19][20][21][22][23][24][25][26] the array of mutually-injected fiber lasers adopts multiple output ports. Then, each output port only needs to burden the power of one elementary laser, and the power scaling of the whole array may not be limited.…”

Fiber laser coherent array for power scaling, bandwidth narrowing, and coherent beam direction control

“…Coherent beam combining of many fiber lasers is an important and challenging research topic for power scaling of single-mode fiber laser as well as for developing highly-functional fiber laser [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16]. Achieving a single output of both high-power and high-brightness from many moderate-power lasers as well as coherent control of beam deflection without mechanical movements are goals which will promise a great number of scientific and industrial applications.…”