Experimental study of a new kind of gas-flowing diode pumped cesium laser

Abstract

A diode pumped alkali laser (DPAL) provides a significant potential for construction of high-powered lasers. To realize the scaling of a DPAL, heat management should be optimized. In this paper, a new kind of gas-flowing DPAL was proposed, in which a small cross-flow fan with diameter of 125 mm was set in the center of a cylindrical vapor cell whose diameter and thickness is 160 mm and 55 mm, respectively. The gain medium of cesium and the buffer gas of ethane were filled in the vapor cell with the total pressure is about 1 atmosphere. A mathematical model was constructed to systematically study the influence of the rotate speed on the internal temperature distribution and the output features of the laser. And then, the experimental study of the laser system was then carried out, in which the output laser at 894.3 nm with power of 32 W was obtained. The results show that both the velocity distribution and temperature distribution are greatly influenced by the rotate speed of the cross-flow fan, and then the heat generated from the DPAL can be took away efficiently, which is very important to the output performance of the laser system. These results indicate that this new type of gas-flowing DPAL might be a good choice for power scaling of DPALs.

Investigation of a flowing-gas Cs laser with a disc-type vapor cell

“…It can be seen that the temperature decreases lightly with the rotate speed of a fan increases from 1000 to 5000 r/min. This result is in agreement with the previous theoretical study [12], suggesting that the increase of rotate speed of a cross-flow fan can effectively decrease the temperature difference of the alkali vapor inside the vapor cell, but has little influence on the mean temperature of the whole cell. The influence of rotate speed of a cross-flow fan on output power was then studied.…”

“…To solve the above problem, a novel compact disc-type vapor cell was introduced in our Cs-DPAL, in which the gas flowing was driven by a cross-flow fan installed at the center of the vapor cell. To the best of our knowledge, the first demonstration of this kind of DPAL is our recent work [12]. In this paper, we extend our work by presenting the experimental results of a flowing-gas Cs laser.…”