Pantis-Simut Calin-Andrei, Preda Amanda Teodora, Filipoiu Nicolae, Allosh Alaa, Nemnes George Alexandru
Horia Hulubei National Institute for Physics and Nuclear Engineering, 077126 Magurele-Ilfov, Romania.
Faculty of Physics, University of Bucharest, 077125 Magurele-Ilfov, Romania.
Nanomaterials (Basel). 2022 Oct 18;12(20):3650. doi: 10.3390/nano12203650.
Phosphorene is a graphene-like material with an intermediate band gap, in contrast to zero-gap graphene and large-gap dichalcogenides or hexagonal boron nitride (hBN), which makes it more suitable for nanoelectronic devices. However, inducing band-gap modulation in freestanding phosphorene nanoribbons (PNRs) is problematic, as high in-plane electric fields are necessary to close the gap. We perform here a detailed investigation concerning the substrate influence on the electric-field control exerted by an external gate, using the density functional theory-non-equilibrium Green's functions (DFT-NEGF) framework. It is established that the interaction with a hexagonal boron nitride supporting layer significantly enhances the gap modulation. Furthermore, we address the issue of contacting the PNRs, by using conducting graphene nanoribbons embedded in the support hBN layer. Within this setup, a measurable spin polarization is achieved owing to the anti-ferromagnetic coupling between the edges of the graphene nanoribbons.
与零带隙的石墨烯以及宽带隙的二硫族化合物或六方氮化硼（hBN）不同，磷烯是一种具有中间带隙的类石墨烯材料，这使得它更适合用于纳米电子器件。然而，在独立的磷烯纳米带（PNR）中诱导带隙调制存在问题，因为需要高面内电场来关闭带隙。我们在此使用密度泛函理论 - 非平衡格林函数（DFT - NEGF）框架，对衬底对外部栅极施加的电场控制的影响进行了详细研究。结果表明，与六方氮化硼支撑层的相互作用显著增强了带隙调制。此外，我们通过使用嵌入支撑hBN层的导电石墨烯纳米带来解决PNR的接触问题。在这种设置下，由于石墨烯纳米带边缘之间的反铁磁耦合，实现了可测量的自旋极化。
