Khani H, Esmaeilzadeh M, Kanjouri F
Department of Physics, Kharazmi University, 31979-37551, Tehran, Iran.
Phys Chem Chem Phys. 2017 May 31;19(21):14170-14177. doi: 10.1039/c6cp08817a.
Generation of large currents, versatile functionality, and simple structures are of fundamental importance in the development of adiabatic quantum pump devices with nanoscale dimensions. In the present study, we propose an adiabatic quantum pump with a simple structure based on molybdenum disulfide, MoS, to generate large spin and valley resolved currents. We show that pure and fully polarized spin and valley currents can be easily generated by employing two potential gates and using an exchange magnetic field. Unlike graphene and silicene, in order to induce a valley resolved current in MoS, one does not need to induce strain and apply an electric field. The spin and valley resolved currents are completely coupled together, so that the spin up (down) current is exactly equal to the valley K(K') current. Hence, we can detect the valley resolved current by utilizing more straightforward and simple methods used for the detection of spin resolved currents. The other prominent feature of this proposed pump is its large current, which is two and three orders of magnitude larger than the maximum current of similar pump structures based on silicene and graphene, respectively. The results of this study are promising for the fabrication of quantum pumps with large spin and valley resolved currents, which opens up the possibility of further development of spintronics and valleytronics in 2D nanostructures.
产生大电流、具备多功能性以及拥有简单结构，对于纳米尺度绝热量子泵器件的发展至关重要。在本研究中，我们提出了一种基于二硫化钼（MoS）的结构简单的绝热量子泵，以产生大的自旋和谷分辨电流。我们表明，通过使用两个电势门并施加交换磁场，可以轻松产生纯的且完全极化的自旋和谷电流。与石墨烯和硅烯不同，为了在MoS中诱导出谷分辨电流，无需施加应变和电场。自旋和谷分辨电流完全耦合在一起，使得自旋向上（向下）电流恰好等于谷K（K'）电流。因此，我们可以通过利用用于检测自旋分辨电流的更直接、更简单的方法来检测谷分辨电流。该提议的泵的另一个突出特点是其大电流，分别比基于硅烯和石墨烯的类似泵结构的最大电流大两个和三个数量级。这项研究的结果对于制造具有大自旋和谷分辨电流的量子泵很有前景，这为二维纳米结构中自旋电子学和谷电子学的进一步发展开辟了可能性。
