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Entry  Tue Mar 30 21:11:42 2010, kiwamu, Summary, Green Locking, conversion efficiency of PPKTP efficiency_waist_edit.png
    Reply  Tue Mar 30 22:13:49 2010, Koji, Summary, Green Locking, conversion efficiency of PPKTP 
       Reply  Wed Mar 31 11:52:32 2010, kiwamu, Summary, Green Locking, Re:conversion efficiency of PPKTP 
Message ID: 2740     Entry time: Wed Mar 31 11:52:32 2010     In reply to: 2736
Author: kiwamu 
Type: Summary 
Category: Green Locking 
Subject: Re:conversion efficiency of PPKTP 

Good point. There is a trick  to avoid a divergence.

Actually the radius of the cylindrical wave is set to the spot size at the surface of the crystal instead of an actual beam waist. This is the idea Dmass told me before.

So that the radius is expressed by w=w0(1+(L/2ZR)2)1/2, where w0 is beam waist, L is the length of the crystal and ZR is the rayleigh range.

In this case the radius can't go smaller than w0/2 and the solution can not diverge to infinity.



Why does the small spot size for the case (A) have small efficiency as the others? I thought the efficiency goes diverged to infinity as the radius of the cylinder gets smaller.




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