Huang Yen-Chieh, Wang Tsong-Dong, Lin Yen-Hou, Lee Ching-Han, Chuang Ming-Yun, Lin Yen-Yin, Lin Fan-Yi
Institute of Photonics Technologies, Department of Electrical Engineering, National Tsinghua University, Hsinchu 30013, Taiwan.
Opt Express. 2011 Nov 21;19(24):24577-82. doi: 10.1364/OE.19.024577.
We report forward and backward THz-wave difference frequency generations at 197 and 469 μm from a PPLN rectangular crystal rod with an aperture of 0.5 (height in z) × 0.6 (width in y) mm(2) and a length of 25 mm in x. The crystal rod appears as a waveguide for the THz waves but as a bulk material for the optical mixing waves near 1.54 μm. We measured enhancement factors of 1.6 and 1.8 for the forward and backward THz-wave output powers, respectively, from the rectangular waveguide in comparison with those from a PPLN slab waveguide of the same length, thickness, and domain period under the same pump and signal intensity of 100 MW/cm(2).
我们报道了利用孔径为0.5（z方向高度）×0.6（y方向宽度）mm²、x方向长度为25mm的周期极化铌酸锂（PPLN）矩形晶体棒，产生197μm和469μm的太赫兹（THz）波前向和后向差频。该晶体棒对于太赫兹波表现为波导，而对于1.54μm附近的光混频波则表现为体材料。在相同的100MW/cm²泵浦和信号强度下，与相同长度、厚度和畴周期的PPLN平板波导相比，我们测量了矩形波导前向和后向太赫兹波输出功率的增强因子分别为1.6和1.8。
