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K301V 125W CW Nd:YAG pumping chamber for sale

Alaskan

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I wonder about the NLO crystal needed to produce 589 nm, if I understand correctly, each crystal needs to be cut at the correct angle for a specific SHG frequency, then, to minimise losses, AR coated for accept BB 1064 and 1319 nm on the input side, and AR coated for 589 nm on the output side of the crystal. Do I have these concepts correct?
 

CurtisOliver

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Yes they do need to be cut at the right angle. But more importantly phase matched at the right angle. AR coating is also very important for weak lines and of course helps boost the optical efficiency.
 

Alaskan

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OK, cut at the correct angle for 589 nm and then either the crystal, or the polarized output of the YAG turned so the phase is matched to the crystal, is that all stated correctly?
 

CurtisOliver

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Sorry, I mistakenly wrote that they have to be cut at the right angle, while this technically is true, they need to be cut on the right plane. Then the angle is actually the phase angle of which you must align on the optical axis. There are two axes that need to referenced and are often referred to as phi and theta.
 
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diachi

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OK, cut at the correct angle for 589 nm and then either the crystal, or the polarized output of the YAG turned so the phase is matched to the crystal, is that all stated correctly?
Keep in mind YAG is going to be randomly polarized without a polarizer/brewster window/brewster cut rod.

Sorry, I mistakenly wrote that they have to be cut at the right angle, while this technically is true, they need to be cut on the right plane. Then the angle is actually the phase angle of which you must align on the optical axis. There are two axes that need to referenced and are often referred to as phi and theta.

Good info. :beer:
 

Encap

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I have a coworker like that, exactly that, I hate being around him because of it! So how is it done to keep 1064 nm from doing that? Put a pass filter which allows more of that than 1064? Or perhaps a mirror which has far higher reflectivity to 1319 nm?
Alaskan: This actilce might be an interesting read for you.

Single-pass sum-frequency-generation of 589-nm
yellow light based on dual-wavelength Nd:YAG
laser with periodically-poled LiTaO3 crystal

Abstract: We demonstrate a compact all-solid-state yellow laser source
based on Q-switched dual-wavelength Nd:YAG laser and periodically-poled
LiTaO3 crystal. 589-nm yellow light was generated by single-pass sumfrequency
generation of the fundamental IR waves at 1064 and 1319 nm.
The maximum output power of yellow light was 506 mW and the
corresponding conversion efficiency was ~5.5% [W−1cm−1].

See: https://www.osapublishing.org/DirectPDFAccess/44F96C86-9C75-2FB9-686523764E08F8A1_201810/oe-18-13-13331.pdf?da=1&id=201810&seq=0&mobile=no
and this one
Laser diode pumped Nd:YAG crystals frequency summing 589nm yellow laser
Abstract
We report the efficient compact 589-nm yellow laser generation by intra-cavity sum-frequency of a continuous wave (cw) laser operation of a diode-pumped double Nd:YAG crystals at 1064 nm and 1319 nm. An LiB3O5 (LBO) crystal, cut for critical type I phase matching at room temperature, is used as the nonlinear optical crystals for frequency summing. A maximum output power of 102 mW in the yellow spectral range at 589 nm was achieved at an incident pump power of 2 W. In 40 min we achieved an optical-to-optical conversion efficiency of 5.1% with a power instability less than 5.66%, the configuration is compact, flexible and efficient
See: https://www.researchgate.net/publication/284012669_Laser_diode_pumped_NdYAG_crystals_frequency_summing_589nm_yellow_laser


You need an account for the last one unfortunately.
 
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CurtisOliver

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+rep for the article Encap. I do believe it will be easier and cheaper with a KTP crystal however. Crystal ovens are expensive and I don't know where you can source LiTaO3 coated for 1064+1319. It may have to be a custom job. Either way though the single pass nature of the article is very appealing.

Edit: Thanks for the update.
 
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Encap

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+rep for the article Encap. I do believe it will be easier and cheaper with a KTP crystal however. Crystal ovens are expensive and I don't know where you can source LiTaO3 coated for 1064+1319. It may have to be a custom job. Either way though the single pass nature of the article is very appealing.
Your right is a difficult way to go.

This guy gives some good background and does YAG>KTP 589nm generation.

"The advantage of this approach
lies primarily on its simplicity: the 1064
and 1319 nm lines are generated simultaneously
from an Nd:YAG laser, and at the same time the
intracavity SFG at 589 nm is generated with a type
II KTP crystal."
See: http://nano.aalto.fi/en/midcom-serveattachmentguid-1e585fc43fbf4d085fc11e5a5b4712821f4030d030d/2012_5.pdf
 

CurtisOliver

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Yes, that is the more accepted way of producing high output 589. I see they use two separate yag's to produce the 1064 and 1319 lines. This is probably due to the difficulty of producing high amounts of 1319 in the same crystal as the 1064.
Anyway, the LD 808 pump power was 171W, but I guess Alaskan can easily double that. :p
 

Alaskan

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Seems to me the direction I want to go in this hobby is to produce a relatively high power output 589 nm laser using a ND:YAG summing 1064 and 1319 into a NL crystal. Which crystal, which optics, two rods, one for each IR WL or what, I don't know. How to best combine the two outputs, dichro? Probably would flash the coatings away, depending.

Tks for the links, I will research them to look for more info.
 

CurtisOliver

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Seems to me the direction I want to go in this hobby is to produce a relatively high power output 589 nm laser using a ND:YAG summing 1064 and 1319 into a NL crystal.
I would never of guessed. :p
Which crystal, which optics, two rods, one for each IR WL or what, I don't know. How to best combine the two outputs, dichro? Probably would flash the coatings away, depending.

Tks for the links, I will research them to look for more info.
These are things you will have to think about depending on how large a system you are designing. If you want very high output, then two separate yag's could be the way to go. Then you would need to create cavities for each of the yags, and then combine them. You also have to consider the low damage threshold of KTP.
 

Alaskan

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KTP does have higher efficiency, but for damage threshold maybe LBO is what I need, if such can can be used, need to research.
 

CurtisOliver

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LBO does have a higher damage threshold but you have to remember that it is hygroscopic. Special handling is required. KTP is more tolerant to outside conditions and is more efficient, you just have to have a smaller beam intensity (wider beam) going into it to get around the threshold.
 
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CurtisOliver

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I'm afraid so. It isn't easy to design dpss's as there is so many factors to account for. Even harder with sfg's.
 




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