Comprehensive analyses of the thermal insensitive noncollinear phase-matching for power scalable parametric...

Thermal-induced phase-mismatch distortion, which will dramatically deteriorate the efficient energy transfer, has become a critical obstacle to power scaling of optical parametric amplifiers. To ease this efficiency deterioration, the noncollinear optical parametric amplification (OPA) configuration widely employed to achieve broadband phase-matching (PM) may also serve as a promising approach to optimize the temperature acceptance. In this paper, starting from the noncollinear wave-vector equations, a required thermo- and angle-relationship analogous to that of noncollinear broadband PM is firstly inferred. Based on the presented mathematical criterion, we have explored the potential spectral boundaries of this ingenious temperature insensitive OPA scheme. Full-dimensional simulations of two types of typical OPA processes were quantitatively discussed. Compared with traditional collinear PM designs, the presented noncollinear PM configurations show significant common characteristics on improving the temperature acceptance and subsequently the overall amplification efficiency. For a typical high power parametric process of the 532 nm pumped near-IR OPA at 800 nm especially, incredible temperature bandwidth exceeding 8000 °C was obtained while a YCOB (xz plane) crystal is adopted. What is more, it can also be applied to ameliorate the gain-spectrum thermo-instability of OPA.