<title>Phased multichannel laser systems with high spatial emission brightness</title>

Abstract

The phase-locked multichannel Nd:YAG laser systems with the long- and short-range coupling via the holographic gain gratings in the active elements are developed. The phase locking of various lamp- and diodepumped loop Nd:YAG lasers with an interference contrast of the laser channels of up to 0.87 and a singlemode lasing efficiency of up to 20% is experimentally demonstrated. The experimental results for the twoand three-channel laser systems are generalized on multichannel laser systems using the numerical simulation. It is demonstrated that the maximum number of the short-range-coupled laser channels can be increased owing to the leveling of the parameters of laser channels to a value that is greater than that the maximum number of the channels in the presence of the long-range coupling, which is limited by the damage threshold of the active element of the interchannel coupling. Use of the multi-loop configuration of the laser resonator allows compensating not only phase distortions but also a gradient of gain in the diode side-pumped active elements.