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Robust half-metallicity and topological aspects in two-dimensional Cu-TPyB.

ABSTRACT: Half-metallicity due to the coexistence of metallic nature for one spin component and insulating nature for the other is a base of spintronics devices, but was only achieved in few materials. From first-principles calculations, we demonstrate that a recently-synthesized two-dimensional organometallic framework of 1,3,5-tris(pyridyl)benzene and Cu atoms (Cu-TPyB) has robust half-metallicity. High electron velocity in one spin channel at Dirac point and a relatively large band gap in the other make the material meeting the demand of filtering the current into a single spin component. Moreover, spin-orbit coupling induces topologically nontrivial band gaps in the vicinity of the Fermi level, which are implementable for achieving quantum anomalous Hall effect in a low temperature range (<8?K).

SUBMITTER: Zhang X

PROVIDER: S-EPMC4568493 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature

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Robust half-metallicity and topological aspects in two-dimensional Cu-TPyB.

Zhang Xiaoming X Zhao Mingwen M

Scientific reports 20150914

Half-metallicity due to the coexistence of metallic nature for one spin component and insulating nature for the other is a base of spintronics devices, but was only achieved in few materials. From first-principles calculations, we demonstrate that a recently-synthesized two-dimensional organometallic framework of 1,3,5-tris(pyridyl)benzene and Cu atoms (Cu-TPyB) has robust half-metallicity. High electron velocity in one spin channel at Dirac point and a relatively large band gap in the other mak ...[more]

PMID: 26365292

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