Abstract By cutting γ-graphyne along different directions, two kinds of γ-graphyne nanodots (γ-GYNDs) can be acquired. In present study, using the γ-GYNDs we theoretically designed and investigated the spin-dependent transport properties of two kinds of molecular magnetic tunnel junctions (MMTJs). Depending on the orientation of γ-GYND and the connection way between γ-GYND and electrodes, our results show that two kinds of MMTJs have different microscopic transport mechanisms. Significant single or dual spin-filtering effects, giant magnetoresistances (reach 108%) and spin negative differential resistances can be observed in the MMTJs. In addition, the spin-polarized optoelectronic properties of the MMTJs have also been discussed, and the results indicate that the spin-polarized photocurrents are dependent on the polarization direction of light and magnetization directions of the electrodes. Especially, two different light-generated spins can be simultaneously produced in the MMTJs if the incident photons have given energies and they flow along opposite directions. The above findings show that the γ-graphyne-based MMTJs can be used as spintronic devices or opto-spintronic devices.

中文翻译：

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γ-石墨烯基分子磁隧道结的输运和光电特性

摘要 通过沿不同方向切割γ-石墨烯，可以获得两种γ-石墨烯纳米点（γ-GYNDs）。在目前的研究中，我们使用 γ-GYND 从理论上设计并研究了两种分子磁隧道结 (MMTJ) 的自旋相关输运特性。根据 γ-GYND 的取向以及 γ-GYND 与电极之间的连接方式，我们的结果表明两种 MMTJ 具有不同的微观传输机制。在 MMTJ 中可以观察到显着的单或双自旋过滤效应、巨磁阻（达到 108%）和自旋负微分电阻。此外，还讨论了 MMTJ 的自旋极化光电特性，结果表明自旋极化的光电流取决于光的极化方向和电极的磁化方向。特别是，如果入射光子具有能量并且它们沿相反方向流动，则可以在 MMTJ 中同时产生两种不同的光生自旋。上述发现表明基于γ-石墨烯的MMTJs可用作自旋电子器件或光自旋电子器件。