This paper shows a novel design for a true zero-order wave-plate to introduce an accurate phase retardation with a big birefringent crystal. The true zero-order wave-plates can be processed with different angles deviating from the crystal’s axis, and the thickness could be selected from millimeter to centimeter order, which increased the mechanical strength greatly. The true zero-order wave-plates were made of NH4H2PO4 (ADP) crystal, including half wave-plate (HWP) and quarter wave-plate (QWP). When the cutting angle θ is 4o, the thickness d of 1064 nm TZ half wave plate (HWP) is 2.75 mm. At the room temperature (25°C), its extinction ratio as the polarization rotator reaches 1000:1 at 1064nm by using spectroscopic method. With ADP-QWP, a 18.6 ns pulse output of Q-switched Nd:YAG laser (1064nm) is successively realized. When the static energy is 160 mJ, the dynamic energy reaches 113 mJ. The above contents provide not only good references for wave-plates fabrication of other birefringent crystals, but also more potential applications in largediameter optical systems such as ultra-high power laser, high resolution inspection equipment and astronomical observation equipment with a large-diameter ADP wave-plate.
Almost all attention has been paid to the effective nonlinear coefficient along the direction of phase matching, so this paper calculated the omnidirectional effective nonlinear coefficient of ReCOB single crystals by computer out of interest. The results showed that the distribution of the first and second quadrants of omnidirectional |deff| presented multi-peaks surface divided by three “valleys” which were made up of a series of minimum values. The variation of d32 and d13 had more significant impacts on the distribution of omnidirectional |deff| than the other coefficients and the variation of wavelength had negligible influence on that. A broadband wavelength range about 6 nm could achieve efficient frequency conversion simultaneously within the deviation being less than 2 degrees during a type-I DFG process in YCOB crystal. These results could provide valuable guidance for the selection and utilization of ReCOB crystals.
YCa4O(BO3)3 (YCOB) was found to have a large temperature bandwidth in XZ optical principal plane. By considering the thermal rotation effect, the temperature bandwidth in spatial directions were studied by theoretical derivation and frequency doubling experiments. The temperature bandwidth in maximum effective nonlinear optical coefficient (deff) direction was not as big as that in (30.8°, 180°) direction. The light propagate in the second quadrant was found to have bigger temperature bandwidth than the first quadrant. And the temperature bandwidth was found to change as the wavelength change of fundamental frequency light.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.