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3d Transition Metal Adsorption Induced the valley-polarized Anomalous Hall Effect in Germanene.

ABSTRACT: Based on DFT?+?U and Berry curvature calculations, we study the electronic structures and topological properties of 3d transition metal (TM) atom (from Ti to Co) adsorbed germanene (TM-germanene). We find that valley-polarized anomalous Hall effect (VAHE) can be realized in germanene by adsorbing Cr, Mn, or Co atoms on its surface. A finite valley Hall voltage can be easily detected in their nanoribbon, which is important for valleytronics devices. Moreover, different valley-polarized current and even reversible valley Hall voltage can be archived by shifting the Fermi energy of the systems. Such versatile features of the systems show potential in next generation electronics devices.

SUBMITTER: Zhou P

PROVIDER: S-EPMC4911552 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

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3d Transition Metal Adsorption Induced the valley-polarized Anomalous Hall Effect in Germanene.

Zhou P P Sun L Z LZ

Scientific reports 20160617

Based on DFT + U and Berry curvature calculations, we study the electronic structures and topological properties of 3d transition metal (TM) atom (from Ti to Co) adsorbed germanene (TM-germanene). We find that valley-polarized anomalous Hall effect (VAHE) can be realized in germanene by adsorbing Cr, Mn, or Co atoms on its surface. A finite valley Hall voltage can be easily detected in their nanoribbon, which is important for valleytronics devices. Moreover, different valley-polarized current an ...[more]

PMID: 27312176

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