论文标题
GAAS支持的石墨烯上的单分子磁铁Mn $ _ {12} $：第一原理的门场效应
Single-Molecule Magnet Mn$_{12}$ on GaAs-supported Graphene: Gate Field Effects From First Principles
论文作者
论文摘要
我们研究门口对Mn $ _ {12} $ o $ $ _ {12} $（COOH）$ _ {16} $（H $ _2 $ O）$ _ 4 $ |石墨烯| GAAS异质结构通过第一原理计算。我们发现，在适度的掺杂水平下，电子可以添加到但不能取自单分子磁铁Mn $ _ {12} $ o $ $ $ $ _ {12} $（COOH）$ _ {16} $（H $ _2 $ O）$ _ 4 $（Mn $ _ {12} $）。 Mn $ _ {12} $的磁各向异性能量（MAE）随着电子掺杂水平的增加而减小，由于电子从石墨烯转移到Mn $ _ {12} $，并且Mn $ _ {12} $ _ {12} $和Graphene之间的频段对齐变得变化。在$ -5.00 \ times 10^{13} \，\ textrm {cm}^{ - 2} $的电子掺杂水平上，MAE降低了约18％。石墨烯和GAA之间的频带对齐对电子掺杂比对孔掺杂更敏感，因为GAA的价带接近费米水平。 GAAS底物在零门场下的受支持石墨烯中诱导一个小带隙和几乎没有应变的配置。最后，我们提出了一个垂直隧道连接点，用于通过电子传输测量值探测MAE的门依赖性。
We study gate field effects on the Mn$_{12}$O$_{12}$(COOH)$_{16}$(H$_2$O)$_4$ | graphene | GaAs heterostructure via first-principles calculations. We find that under moderate doping levels electrons can be added to but not taken from the single-molecule magnet Mn$_{12}$O$_{12}$(COOH)$_{16}$(H$_2$O)$_4$ (Mn$_{12}$). The magnetic anisotropy energy (MAE) of Mn$_{12}$ decreases as the electron doping level increases, due to electron transfer from graphene to Mn$_{12}$ and change in the band alignment between Mn$_{12}$ and graphene. At an electron doping level of $-5.00 \times 10^{13}\, \textrm{cm}^{-2}$, the MAE decreases by about 18% compared with zero doping. The band alignment between graphene and GaAs is more sensitive to electron doping than to hole doping since the valence band of GaAs is close to the Fermi level. The GaAs substrate induces a small bandgap in the supported graphene under the zero gate field and a nearly strain-free configuration. Finally, we propose a vertical tunnel junction for probing the gate dependence of MAE via electron transport measurements.
