Single-molecule magnet Mn12 on GaAs-supported graphene: Gate field effects from first principles

Article

关键词: HIGH-SPIN MOLECULES;    ELECTRON REDUCTION PRODUCT;    STRUCTURAL-CHARACTERIZATION;    MN-12 FAMILY;    ANISOTROPY;    MN12O12(O2CR)(16)(H2O)(4);    PSEUDOPOTENTIALS;    RECONSTRUCTIONS;    GAAS(100);    CLUSTERS;   

DOI  :  10.1103/PhysRevB.105.035401

来源: SCIE

【 摘 要 】

We study gate field effects on the heterostructure Mn12O12(COOH)16(H2O)4|graphene|GaAs via firstprinciples calculations. We find that under moderate doping levels, electrons can be added to but not taken from the single-molecule magnet Mn12O12(COOH)16(H2O)4 (Mn12). The magnetic anisotropy energy (MAE) of Mn12 decreases as the electron-doping level increases due to electron transfer from graphene to Mn12 and change in the band alignment between Mn12 and graphene. At an electron-doping level of -5.00 x 1013 cm-2, the MAE decreases by about 18% compared with zero doping. The band alignment between graphene and GaAs is more sensitive to electron doping than to hole doping, since the valence band of GaAs is close to the Fermi level. The GaAs substrate induces a small band gap in the supported graphene under zero gate field and a nearly strain-free configuration. Finally, we propose a vertical tunnel junction for probing the gate dependence of MAE via electron transport measurements.

【 授权许可】

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