Significant variation of structural, electronic, magnetic, and polarized properties induced by strain in armchair MoSTe nanoribbon

Abstract

Both the inner strain and external strain are considered to study the variation of structural, electronic, magnetic, and polarized properties of aMoSTe-nanoribbons (NRs). Our results show that the aMoSTe-NR presents direct bandgap and magnetism due to the inner strain. With the increase of width, the bandgaps, magnetic moments, and out-of-plane piezoelectronic coefficients present oscillation behavior independence of nanoribbon symmetry. However, the variation of in-plane piezoelectronic coefficients is strongly dependent on the edge type that the aMoSTe-NR with symmetric edges has larger piezoelectronic coefficients than that with asymmetric edges. When the external strain is applied to aMoSTe-NRs, the changes of bandgap, magnetic moment, and polarization are only influenced by the external strain, unrelative to the edge type. Especially, the in-plane polarization is increased accompanied with parabolic behavior in the range from 0 to 8%. The in-plane piezoelectric coefficient is enhanced to 14.072 × 10−10 C m−1 at 8%, about 2.7 times as much as aMoSTe-NRs without strain. The polarization along the out-of-plane direction presents linear character. The Born-effective charge indicates that the polarization of aMoSTe-NRs is mainly from S atoms near edge atoms. The significant variation provides guidance to the application of aMoSTe-NRs in designing electronic and piezoelectric devices.