DAP:NP晶體產生兆赫波輻射之研究

Abstract

DAP:NP晶體(全名為2,6-diaminopyridine-4-nitrophenolate-4-nitrophenol)為一新穎的有機非線性光學材料，本論文首次利用超短脈衝雷射激發DAP:NP晶體使其產生兆赫波輻射，並利用一系列方位角相依的兆赫波信號量測來釐清兆赫波產生的機制，研究結果顯示DAP:NP晶體的兆赫波產生機制為光整流效應，這與理論計算的結果一致。除此之外，透過X-ray繞射儀、UV-VIS-NIR光譜儀、二倍頻量測系統等儀器，我們亦對DAP:NP晶體的晶體結構、光學特性有更深入的認識。

DAP:NP(2,6-diaminopyridine-4-nitrophenolate-4-nitrophenol) crystals are the new organic nonlinear optical materials. In this study, we have firstly generated the THz radiation from DAP:NP crystals by using femtosecond laser pulses. The amplitude of THz radiation is strongly dependent on the azimuthal angle of DAP:NP crystals and show the six-fold symmetry with the configuration of P-polarized pump and P-polarized probe (Ppump-Pprobe), two-fold symmetry with the configuration of S-polarized pump and P-polarized probe (Spump-Pprobe). These results indicate that the THz generation mechanism is optical rectification, which is also consistent with the theoretical calculations. Moreover, the crystal structure and optical properties of DAP:NP crystals were also studied by the x-ray diffractometer, UV-VI-NIR spectrometer, and second harmonic generation system.