Enhanced Valley Zeeman Splitting in Fe-Doped Monolayer MoS2
Enhanced Valley Zeeman Splitting in Fe-Doped Monolayer MoS2
复制标题
Fe 掺杂单层 MoS2 中增强的谷塞曼分裂
DOI：
10.1021/acsnano.0c00291
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发表时间：
2020-04-28
期刊：
影响因子：
17.1
通讯作者：
Peng, Bo
中科院分区：
文献类型：
--
作者：
Li, Qi;Zhao, Xiaoxu;Peng, Bo
“塞曼效应”为自旋自由度（DOF）的磁操纵提供了独特的机会。最近，在液氦温度下，二维过渡金属二硫化物（TMDs）中发现了谷简并的提升，即谷塞曼分裂。然而，为了实现谷假自旋的实际应用，谷自由度必须在室温下由磁场控制，这仍然是一个重大的挑战。磁掺杂可以增强tmd的塞曼分裂；然而，要在实验上实现这一点并不容易。在这里，我们报道了在cvd生长的fe掺杂MoS2单层中，在300 K （g(eff) = -6.4）和10 K （g(eff) = -11）下的谷塞曼分裂的明确磁操纵；通过增加Fe掺杂浓度，有效朗德g（eff）因子可调至-20.7，与未掺杂的MoS2相比，提高了约5倍。我们的测量和计算表明，分裂和斜翼因子的增强是由于局域磁矩（Fe 3d电子）与MoS2通过d轨道杂化发生海森堡交换相互作用。
The "Zeeman effect" offers unique opportunities for magnetic manipulation of the spin degree of freedom (DOF). Recently, valley Zeeman splitting, referring to the lifting of valley degeneracy, has been demonstrated in two-dimensional transition metal dichalcogenides (TMDs) at liquid helium temperature. However, to realize the practical applications of valley pseudospins, the valley DOF must be controllable by a magnetic field at room temperature, which remains a significant challenge. Magnetic doping in TMDs can enhance the Zeeman splitting; however, to achieve this experimentally is not easy. Here, we report unambiguous magnetic manipulation of valley Zeeman splitting at 300 K (g(eff) = -6.4) and 10 K (g(eff) = -11) in a CVD-grown Fe-doped MoS2 monolayer; the effective Lande g(eff )factor can be tuned to -20.7 by increasing the Fe dopant concentration, which represents an approximately 5-fold enhancement as compared to undoped MoS2. Our measurements and calculations reveal that the enhanced splitting and gaff factors are due to the Heisenberg exchange interaction of the localized magnetic moments (Fe 3d electrons) with MoS2 through the d-orbital hybridization.