The overview of the phase-locking technique is presented. Analysis of the parameters that influence on the phaselocking is given. Admissible range of the deviation of the linear laser diode array, external cavity parameters is estimated. Comparison of the external Talbot cavity configuration with the other ones is held. Attention is paid to both investigation and employment of the laser diode arrays consisting of wide aperture lasers that opens an avenue to high power output radiation in a phase-locked mode. Special consideration is given to the cavity supermodes selection.Our experiments both confirm actual feasibility of 1D and 2D phase-locking of LDA's with specified parameters in the external Talbot (LC=ZT/4) cavity and illustrate theoretical predictions ofthe system stability and selectivity, so that:. phase-locking in 1D configuration allowed difractional limited lobes width W=O.5 mrad;. tiltingof the output mirror provided "in-phase" supermode selection;. phase-locking in 2D configuration of the two LDA's of N=8 lasers, separated by 1600 mkm resulted in diffractional lobes full width at halfmaximum '=O.5 mrad in slow axis and 8'3!=O.25 mrad in fast axis.

The overview of the phase-locking problem for the powerful laser diode arrays is presented. Comparison of the external Talbot cavity configuration with the other ones is held. Attention is paid to both investigation and employment of the laser diode arrays consisting of wide aperture lasers. Such arrays, placed in the external cavity, allow easier solution ofthe scaling up problem that results in the output lobes with both significantly increased power and low divergence.Our experiments confirm feasibility of both QCW and CW phase-locking of the LDA in the external quarter-Talbot (L=Z1/4) cavity at the output power of more than 10 W with the lobes divergence of 8'PO.5 mrad. Employment of the efficient porous heatexchanger along with the system that cancels both induced phase distortions arising due to heat release and existing optical imperfections has allowed a breakthrough in powerful arrays phase-locking.

Highly efficient heat exchangers with uniform temperature distribution based on microchannel and porous structure are developed. The heat exchange efficiency dependence on construction peculiarities of the devices and cooling liquids properties are shown. Basing on the comparison of both experimental results and the numerical simulation, the ways to obtain the device thennal resistance about 0,2 C/W are discussed. Practical neededs for fabrication both linear diode arrays with power more than 1 kW will be observed.Key worlds: laser diode array, microchannel and porous heat sink I . IntroductionOwing to a strong dependence of the output radiation characteristics, device reliability and effective lifetime of the setnicondor lasers on temperature, the heat exchanger is an essential part ofthe construction. Now the microchannel heat exchanger manufactured with the employment of the high thermoconductive materials is the most widespread type of the device design for the powerful semiconductor lasers. It is a rectangular parallelepiped box, fihledhy a slit channels oriented perpendicularly to a plane of the coolled device attachment. Such heat exchanger provides enough uniform cooling with a small hydraulic resistance. It is simple in manufacturing. Most of the heat exchangers for powerful diode lasers are developed on the basis of the mentioned above design.

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A description of the common properties for different phenomena is presented: interference stabilization of Rydberg atoms in a strong electromagnetic field and phase locking of an array of cavities. A comparison of master equations is held for the discussed effects. Analytical expressions for basic parameters of the problems involved are used for quantitative analysis. The analogy established is exploited for the interpretation of a decrease in intracavity losses in the system of two coupled cavities with an increase of the extent of mutual coupling at a slight detuning of the cavity lengths. The expediency of the analogy establishment consists of existing difficulties in experimental confirmation of the principles of Rydberg-atom stabilization.