Cryogenic Diode Laser?

[weeba2kv]

Cool video about laser cooling and effects

 

[ElectroMagneticFreak]

I don't quite understand the physics behind the wavelength shift but that is really cool! That would be really neat to try getting a 638nm within a handheld / pointer to go below 630nm.

It does seem though that you would risk damage just by the expansion and contraction due to the radical temperature change. (Especially Dry Ice...) Has anyone tried lowering their diode's temperature by chilling their pointers and seen a wavelength shift that is visually perceptible to the eye?

 

[Things]

MarioMaster will probably chip in here with more details, but he actually tried this recently with a cryocooler and liquid air on a red diode, and there is definitely a perceptible wavelength shift, but it wasn't that great, and the diode actually stopped lasing.

Here's the vid he posted: https://dl.dropbox.com/u/1181169/000101.mp4

 

[MarioMaster]

I'll have to try this with some other laser diodes, I still have some junky IR and one or two red cmounts leftover from when Heruursciences was peddling his Boston Laser stock.

The Aixiz module red shown in the video stops lasing just before the module gets down to the temperature of the liquid air (somewhere in the area of -300'F)

 

[ElectroMagneticFreak]

Thanks for posting the video, Things.

That is an interesting clip, Mariomaster. Was the diode still working after the freeze?

Not sure if there is any correlation but it almost seemed like the liquid nitrogen started bubbling and sizzling much more right when the diode ceased to lase?

I am curious to know if an IR Diode in a DPSS system could be cooled to effect the end wavelength such as 532nm. If 808nm is cooled to 800nm, would this modify the transformation into 1064nm and or 532nm? I guess the crystals would have to be temperature isolated from the IR diode to not be effected by temperature?

Do the crystals only function when pumped with a specific wavelength or would they double the frequency no matter the input, ie. 1058nm -> 529nm ?

 

[weeba2kv]

All i know is that you need exactly 808 or else no green lasing

 

[Things]

I am curious to know if an IR Diode in a DPSS system could be cooled to effect the end wavelength such as 532nm. If 808nm is cooled to 800nm, would this modify the transformation into 1064nm and or 532nm? I guess the crystals would have to be temperature isolated from the IR diode to not be effected by temperature?

Do the crystals only function when pumped with a specific wavelength or would they double the frequency no matter the input, ie. 1058nm -> 529nm ?

They are designed to be efficient at 1 central wavelength, most green lab lasers have a TEC on both the diode and crystals, but not to cool the diode and stop it overheating, but to tune the wavelength just right for maximum efficiency. So no, it won't work

 

[mojo_1234]

This a crazy guy.

Did you watched the dye laser video of him? One of coolest lasers ever!

-mo-

 

[Fiddy]

wow 1.9W watt out of a run of the mill red diode.

Has he done a 9mm 455nm diode yet? it should get alot darker in dry ice.

 

[weeba2kv]

Every single day i click his channel to see if there are updates , he does / make somes amazing shizzle hope he will add some updates soon.

 

[MarioMaster]

IIRC the blue diodes don't respond to temperature change as much as the red diodes do, has something to do with the composition of the laser diode - PBD would probably know significantly more about why this happens.

The red laser diode does work again after it warms up, for some reason it no longer lases at extremely low temperatures.

 

[planters]

MarioMaster,

I watched your video and I am wondering about a few points. The diode you submerge is mounted in a housing, but I assume that there are no electronics other than the diode being cooled. There is an increase in the V drop as the diode cools (this is directly related to the mechanism that causes the wavelength to blue shift). Is the drive voltage sufficient to allow the diode to operate as the V drop increases? With the P73 @ 739ma the V drop increased from 2.34V to 2.49V when the diode was cooled from RT to -80C. The increase was linear, but I do not know if it remains linear below this.

Because the diode you tested was not destroyed by the cooling, an open short as an expiation for the quenching doesn't work. But, the boiling nearly stops as the laser dims and so either the driver is unable to maintain a current or the semiconductor and the tiny lead wires are providing so little resistance that little heat is generated.

Fiddy,

I will be testing a bunch of different diodes including the 445's and the new greens. And in a few days I will look @ LN2

 

[Cyparagon]

Not sure if there is any correlation but it almost seemed like the liquid nitrogen started bubbling and sizzling much more right when the diode ceased to lase?

Nope. It "bubbles and sizzles" more when the comparatively hot object gets down to temperature. Caused by the Leidenfrost effect. Here's Another example.