Atomic gas and Semiconductor Lasers.

[hhhmortal]

Hi, I want to know what the important quantitative differences between the light produced by an atomic gas laser and that produced by a semiconductor laser are?

I know that produced my atomic gas lasers are low power but high collimation, but semiconductor lasers seem to have higher power? because of stimulated emission?


Thanks.

 

[a-tom-ic]

As far as i know its quite the opposite:
You can have gas lasers, for example CO2-lasers with 20 kW output power, and by contrast semiconductor lasers (single emitter) in the mW to W range. Laserdiode stacks of course allow you to increase your overall power since its combined from individual single emitters.

For the difference in the light, the emission wavelength is different and as far as i know the quality of the laserbeam is higher with gas lasers.

 

[darkwhite87]

semiconductor lasers can be much more efficient because of direct band gap materials. From memory the efficiency of semoconductor lasers is at least 100x better than gas lasers...but the downside of it is it can not handle too high power..or the PN junction will breakdown..

 

[minerva]

Laser diodes are very small, very compact and very efficient.

However, they're relatively limited in the wavelengths that they can directly emit (excluding things like diode-pumped YAG to indirectly create other wavelengths) - IR, red, and more recently violet and blue are the only wavelengths possible straight off the diode.

Gas lasers are quite heavy, bulky, fragile and inefficient - requiring large, bulky power supply electronics and cooling.

For example, the Ar/Kr ion laser I have here consumes ~2000 W of electrical power to generate ~200 mW of light, so it's really just a 1999.8 W electric room heater.

However, it generates a range of different red, yellow, green and blue emissions lines right across the spectrum - the beam that comes out is actually white light. Laser diodes can't do that :)