Bandwidth analysis of type-I optical parametric chirped pulse amplification systems

We propose a set of empirical formulas to describe the signal broadband gain regime and ultra-broadband gain point under a given pump wavelength for a type-I optical parametric chirped pulse amplification (OPCPA) system. These formulas are applied in the usual nonlinear crystals (beta barium borate, potassium dihydrogen phosphate, deuterated potassium dihydrogen phosphate, cesium lithium borate, lithium triborate, and yttrium calcium oxoborate), and the corresponding results agree with numerically calculated ones. The empirical formulas provide guidelines for selecting appropriate crystals or pump wavelengths to design OPCPA for broadband or ultra-broadband gain bandwidths with appointed signal wavelength. (C) 2014 Optical Society of America