Abstract
In this paper, a systematic study of the relationship between nonlinear crystal length and intracavity second-harmonic generation (SHG) using MgO-doped periodically-poled lithium niobate (MgO:PPLN) is presented. The experimental results demonstrate a relationship between the maximum SHG power generated and the full-width at half maximum (FWHM) of the crystal’s temperature tuning curve to the length of the nonlinear optical crystal. It was shown that maximum SHG power increases rapidly with the increase of MgO:PPLN length, reaching a saturation length (~ 2 mm), which is much shorter than that predicted by the single-pass SHG theory. This saturation length of the MgO:PPLN crystal is almost independent on 808 nm pump power for typical powers used in continuous wave intracavity SHG lasers. In addition to this saturation effect, a broadening effect was also observed, the FWHM of the temperature tuning curve was shown to have a larger FWHM than that predicted by the single-pass SHG theory for MgO:PPLN shorter than the saturation length. This work has the benefit of allowing engineers to optimize nonlinear crystal length when developing intracavity SHG based diode-pumped solid state (DPSS) lasers.
Highlights
In this paper, a systematic study of the relationship between nonlinear crystal length and intracavity second-harmonic generation (SHG) using MgO-doped periodically-poled lithium niobate (MgO:PPLN) is presented
The main novelty of this paper is to present a systematic study of PPLN length versus maximum SHG output power for compact, watt-level green SHG lasers
Have strong demand in applications such as laser display and biomedical applications. This is an area our research group has worked on extensively[30,31], and the simple cavity structure should serve as a good baseline example of how MgO:PPLN length and fundamental pump power modify the expected maximum SHG output power
Summary
A systematic study of the relationship between nonlinear crystal length and intracavity second-harmonic generation (SHG) using MgO-doped periodically-poled lithium niobate (MgO:PPLN) is presented. An intracavity structure is commonly used to increase the effective interaction length in the nonlinear crystals and the fundamental wave intensity This approach has a number of benefits over the single-pass approach, such as compact form factor, low-cost, and a high conversion efficiency and high output p ower[18,19,20,21,22,23,24,25,26,27,28,29]. Have strong demand in applications such as laser display and biomedical applications This is an area our research group has worked on extensively[30,31], and the simple cavity structure should serve as a good baseline example of how MgO:PPLN length and fundamental pump power modify the expected maximum SHG output power
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
