title: Broadening of the second-harmonic phase-matching bandwidth in type II periodically poled KTP.
abstract: We have theoretically demonstrated type II broadband second-harmonic generation (SHG) based on a quasi-phase-matching (QPM) configuration in periodically poled KTP (PPKTP). The wavelength dependence of QPM grating periods at different temperatures of 5 degrees C, 25 degrees C, and 45 degrees C is calculated with the crystal length of 1 cm. We find a very wide bandwidth, as large as 42.6 nm, of fundamental wavelength of 1.58 microm at the telecommunication band with the QPM period of 48.9 microm at 25 degrees C. The corresponding bandwidths of incident angle and temperature are found to be 4.24 degrees and 14.8 degrees C, respectively. The comparison among PPKTP, periodically poled lithium niobate (PPLN), and MgO:PPLN reveals the unique performance of PPKTP in the broadband SHG.
authors.affiliation: Department of Physics, State Key Laboratory on Fiber Optic Local Area Communication Networks and Advanced Optical Communication Systems, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.
authors.forename: Rui
authors.initials: R
authors.lastname: Wu
authors.forename: Yuping
authors.initials: Y
authors.lastname: Chen
authors.forename: Junfeng
authors.initials: J
authors.lastname: Zhang
authors.forename: Xianfeng
authors.initials: X
authors.lastname: Chen
authors.forename: Yuxing
authors.initials: Y
authors.lastname: Xia