Thermal Effect on Output Power of He-Ne 6328Å Laser

Abstract

In operating He-Ne 6328Å laser with constant DC discharge power we can always find the output power increase for increasing of temperature of He-Ne mixed gas, decreases for decreasing of temperature of He-Ne mixed gas and a cut-off exists for a certain temperature. Keeping the temperature of He-Ne mixed gas remains constant, the output power of the laser will change only with different values of discharge power. As the discharge power increases, the output power first reaches a maximum than falls down and also attains a cut-off. It was discovered and originated by F.T. Arecchi in 1963 that the output power of a He-Ne laser is a function of temperature, discharge power and life times of transition levels. But his assumption："Electron density in active medium is proportional linearly with discharge power."is not applicable in the abnormal glow region of gas discharge where laser action always occurs. Hence the expressions derived by Arecchi must be modified. This paper presents a theory of modification of Arecchi's expressions together with an experimental justification.