(adsbygoogle = window.adsbygoogle || []).push({}); 1. LiNbO3 is a negative uniaxial crystal. Consider a LiNbO3 crystal used for frequency doubling a laser operating at 1064 nm. The non-linear coefficient is d=3.4x10-23. For the setup considered it is desirable to have a non-linear conversion efficiency of 0.04 %/W,

Assume constant fundamental power throughout the crystal. Determine the crystal length required in

i. the plane wave approximation assuming a Gaussian focus waist of 10x10^-6m

Ok, so I have calculated the refractive index n0 and ne and established phase matching is possible in the previous question. Now I was intending to use the equation for the second harmonic intensity to help with calculating the crystal length but my problem is how I calculate the fundamental intensity. I have spent a lot of time on it but I don't feel like I have a very good grasp of the question itself and was hoping for any pointers as to where I should look to begin solving this question.

Thanks

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Frequency doubling of monolithic Nd:YAG laser in external enhancement cavity

**Physics Forums | Science Articles, Homework Help, Discussion**