quasi tensor 中文意思是什麼
quasi tensor
解釋
準張量-
At present, people usually use birefrigence and quasi - phase - matching methods to achieve higher effiency in the process of conversion. a significant advantage of quasi - phase - matching method is that the interaction is occurred through the largest element of the x ( 2 ) tensor ; the period of optical superlattice can be designed randomly, and any interaction can be matched without walk - off angle ; they are fitted to be used in frequency conversion of lower power especially. the quasi - phase - matching method has some advantages over birefrigence method, improving the efficiency of frequency conversion ; the range of frequency conversion covers its whole transperant wavelength
由於準相位匹配技術有其獨特的優勢,可以利用非線性光學晶體的最大二階極化張量,如ppln 、 pplt 、 ppktp用的非線性極化張量都是d _ ( 33 ) ,其有效非線性系數高出普通非線性光學介質(如bbo 、 lbo 、 ktp )一個數量級,而且可以人為靈活設計調制周期,通過周期設計其頻率變換范圍可以覆蓋準相位匹配介質的整個透明波段,選擇無走離效應,解決了常規pm難以解決的問題,拓寬了非線性晶體的應用范圍,極大地提高了頻率轉換效率,已成為非線性光學材料和固體激光器的研究熱點之一。
分享友人