3 ms·

This laser requires a second laser to pump it in order for it to work. It's kind of defeating the point of things.

m-watson 5y ago
A lot of lasers require a pump laser, it seems their argument is that this can be useful for low cost production in something like the telcom world.
jacquesm 5y ago
Not really. Pumped lasers are the norm for quite a few materials that are hard to use as primary light source, but as a secondary lightsource they are plenty useful. Note that lots of other lasers are pumped as well, for instance, some lasers were originally pumped by flashing Xenon light from spiral wound flash tubes into Ruby crystal rods grown at great expense to get the gas to emit coherent light. The energy efficiency is important so that you don't end up overheating your secondary laser but the principle has plenty of uses and isn't even restricted to using light as the starting point. One possible way to use this is to use a somewhat higher power laser to illuminate a substrate at right angles to the desired outputs, which would allow for a hybrid where only the primary is made with exotic materials and the remainder can be made in Silicon. Right now every laser output needs to be on a physically different die than the Silicon based circuitry that drives it, this technique could do away with that intermediary step substantially reducing the costs of certain telecommunications devices. Finally, once something has been pushed to lase it usually doesn't take very long before improvements are made that allow it to do so cheaper, faster or independent of the original light source, it is that first step that is the really hard one. One joke I heard from someone who is deep inside laser research is that when all is said and done there are probably not a whole lot of substances that can't be made to emit coherent light, the trick is to find out how to do it in the first place, and then to do it repeatedly and affordably.

A lot of lasers require a pump laser, it seems their argument is that this can be useful for low cost production in something like the telcom world.

jacquesm 5y ago

Not really. Pumped lasers are the norm for quite a few materials that are hard to use as primary light source, but as a secondary lightsource they are plenty useful. Note that lots of other lasers are pumped as well, for instance, some lasers were originally pumped by flashing Xenon light from spiral wound flash tubes into Ruby crystal rods grown at great expense to get the gas to emit coherent light. The energy efficiency is important so that you don't end up overheating your secondary laser but the principle has plenty of uses and isn't even restricted to using light as the starting point. One possible way to use this is to use a somewhat higher power laser to illuminate a substrate at right angles to the desired outputs, which would allow for a hybrid where only the primary is made with exotic materials and the remainder can be made in Silicon. Right now every laser output needs to be on a physically different die than the Silicon based circuitry that drives it, this technique could do away with that intermediary step substantially reducing the costs of certain telecommunications devices. Finally, once something has been pushed to lase it usually doesn't take very long before improvements are made that allow it to do so cheaper, faster or independent of the original light source, it is that first step that is the really hard one. One joke I heard from someone who is deep inside laser research is that when all is said and done there are probably not a whole lot of substances that can't be made to emit coherent light, the trick is to find out how to do it in the first place, and then to do it repeatedly and affordably.