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uniaxial crystal 【物理學】單軸結晶體。

unicameral

Because of its complexity , no analytic solution can be got . to better understand the propagation characteristics of the waveguide , it is necessary that analytic solution should be got for simpler structure . based on the background , in this paper , we discuss the propagation characteristic of ray in the planar symmetric metal - clad uniaxial waveguide ( the waveguide layer is uniaxial crystal 但是以前人們只局限于對非對稱金屬波導(即在各向異性介質波導層一面上鍍有金屬膜)的討論,由于其復雜性,他們沒有給出解析解,為了能更好的解析討論其傳輸特性,需要討論較簡單的波導結構。

The most achievement is that we firstly obtain the analytic accurate solution of the modal fields of the waveguide structure and find some available character : ( 1 ) the different uniaxial crystal materials have the different propagation properties ; ( 2 ) when the optical axis of the crystal is on the plane that is made up of the normal direction of the waveguide plane and the propagation , there are te mode and tm mode in this special waveguide , but the principal mode is different of the character of the uniaxial crystal , the principal mode is the principal mode of te mode for the negative uniaxial crystal , but the one of tm mode for the positive uniaxial crystal ; ( 3 ) when the crystal optical - axis parallel to the waveguide plane , for the positive uniaxial crystal material , the principal mode of the waveguide is a te wave , which can be excited by the light at any frequency ; when the light frequency satisfies a single mode propagation condition , there will be only the principal mode propagating in the waveguide , otherwise some of the higher order modes can be excited , which are neither te modes , nor tm modes , but the hybrid guided modes 本文就是在此背景下,利用金屬波導和單軸晶體的一些特性,結合麥克斯韋方程組和波導的邊界條件,從三種不同的情況研究了光在對稱平面單軸晶體金屬波導(波導層是單軸晶體,兩個波導界面均為金屬)內的傳輸特性,其主要貢獻為,首次解析地得到了這種波導結構下模式場的精確解,并發現了一些有用的特性: ( 1 )模式場的性質因單軸晶體的性質不同而異; ( 2 )當單軸晶體光軸位于波導界面法方向與傳輸方向構成的平面內時,波導中傳輸te波和tm波,只不過其主模因單軸晶體的性質不同而異,當波導層介質為負單軸晶體時,波導主模是te波主模,而波導層介質為正單軸晶體時波導主模是tm波主模。 ( 3 )當單軸晶體光軸位于波導面內時,對于正單軸晶體,波導的主模是橫電波te _ 0模,任何頻率的光波均可激勵該模式;當光波波長滿足一定條件時,波導內傳輸單模,否則,將激勵起高階模式,高階模即匪te波,也匪tm波,而是兩者耦合而成的混合模。

For the negative uniaxial crystal material , the principal mode is a hybrid guided mode , which can also be excited by the light at any frequency , but when the single mode propagation condition can not be satisfied , some of the higher order hybrid guided modes will exist in the waveguide 對于負單軸晶體,波導的主模是混合模hgm _ 0模,該模式同樣可被任何頻率的光波所激勵;當光波波長滿足一定條件時,波導內傳輸單模,否則,將激勵起高階混合模。

Not only general suitability of this method is independent of gratings model , geometry structure , medium properly and crystal axis orientation ( including uniaxial crystals and biaxial ones ) , but also physical concepts are clear and formula is concise 該方法不僅不受光柵模型、幾何結構、介質性質和晶體取向(包括單軸和雙軸晶體)的影響而具有普遍適用性,而且其物理概念清晰、公式簡潔。

The coefficients of reflection and transmission on the interface of two uniaxial crystals under normal incidence 正入射條件下光在兩單軸晶體分界面的反射與透射系數