Characterization of a periodically poled lithium niobate optical parametric oscillator pumped by a Bessel beam

A Bessel beam pumped periodically poled lithium niobate optical parametric oscillator has been characterized. A slope efficiency of 5.4 +/- 0.1% was obtained and a threshold pulse energy of 472 +/- 12 mu J was measured, which corresponds to a threshold fluence of 0.207 +/- 0.005 J cm(2). The signal output was tuned over similar to 20 nm by changing the crystal temperature by 50%C. The FWHM bandwidth at each temperature was observed to be 0.3 +/- 0.1 nm at each wavelength. The beam profiles of the Bessel pump and Gaussian signal beams were studied in both the near and far field. A beam divergence of 1.14 +/- 0.02 mrad was measured.