在自旋電子學中，有機材料作為自旋傳輸材料的使用在近年來引起了廣泛的關注，然而在一般的有機材料當中，因為自旋軌道交互作用(spin-orbital interation，SOI)較弱，無法成為較好的材料。因此，自旋極化電流通常由鐵磁性或強自旋軌道交互作用的無機材料產生。
然而，在近年來的諸多論文報告顯示，發現了通過螺旋分子的自旋選擇電子傳輸，也就是所謂的手性誘導自旋選擇性效應(CISS)，他們提出了使用有機材料作為自旋濾波器的另一種方法。
於是本研究使用的有機材料為甘胺酸(glycine)分子，甘胺酸是胺基酸的一種，其主要結構分為兩種(螺旋/直鏈)，再將此胜肽分子來搭建出量子輸運系統，並在其一電極(Ni)施加不同方向的極化方向。利用第一原理對胜肽進行結構優化及電性分析，觀察不同結構的Transmission、LDOS、IVcurve和Junction magnetoconductance(JMC)在兩種自旋極化下的自旋選擇性效應，並比較了各結構的一般物理性質。
根據研究結果，我們發現左旋的電子透射頻譜在費米能階上的數值要大於右旋將近10~100倍，螺旋結構的結磁導率到達了5%，且在電子傳輸能力與電導上，螺旋結構均要高於直鏈結構。然而，關鍵的是我們發現電子在穿過螺旋結構分子的地方，其中一自旋態的自旋電流要高於另一種自旋態，且差別較為明顯;相反的，直鏈結構分子的兩種自旋態差別甚小。其推測主要原因為:螺旋結構相較於直鏈結構，其分子間交互作用力較強，也反映出手性螺旋分子相較於直鏈分子更好的誘發自旋選擇性效應(CISS)。

In spintronics, using organic materials as spin transporting materials has attracted attention in recent years. Although the spin has been investigated extensively, there remains a challenge to utilize spin for electronic application.
However, in general organic materials, the weak spin-orbit interaction (SOI) becomes a disadvantage. Interestingly, It has recently been discovered that the spin-selective electron transmission of the chiral molecule is known as the chiral-induced spin selectivity (CISS) effect. They proposed another method of using organic materials as spin filters.
So the organic material used in this study is glycine molecule, glycine is a kind of amine acid, its main structure is divided into two (helix & straight chain), and then the peptide molecule to build a electronic-transport system, and in one electrode (Ni) to apply a different direction of polarization. Using the first principle to optimize the structure and electro-electrical analysis of the peptide, finally, the spin-selective effects of Transmission, LDOS, Junction magnetoconductance (JMC) and IVcurve of different structures were observed, and the general physical properties of each structure were compared.
According to the results of the study, we find that the value of the electron transmission spectrum of the left-handed is nearly 10 to 100 times greater than that of the right-hand tron, the JMC of the spiral structure reached 5% and the spiral structure is higher than the straight chain structure in the electron transmission capacity and conductivity. Crucially, however, we find that electrons pass through the spiral structure molecules, where one spin current is higher than the other, and the difference is more obvious; The main reason for the speculation: the spiral structure compared to the straight chain structure, its molecular interaction force is strong, but also reflects the chiral molecules than the straight chain molecules better induced spin selectivity (CISS).

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