09:30 〜 11:30
▲ [15a-PA01-35] Spin-mechatronics device based on controllable mass gapped Dirac cone of graphene in a Ni/hBN–graphene–hBN/Ni magnetic junction.
キーワード：graphene, in-plane magnetoresistance, Dirac cone engineering
A first-principles study on Ni/hBN–graphene–hBN/Ni magnetic junction was presented to understand the role of Ni/hBN slab–Graphene interface in controlling mass gapped of graphene Dirac cone (MGDC) via magnetic proximity effect. The spin-polarized density functional theory calculation was performed on three important structures, each corresponding to van der Waals's interaction between hBN and graphene. The calculation was done for both Ni slabs' magnetic alignment configurations, i.e., anti-parallel configuration (APC) and parallel configuration (PC). The first structure, where N atoms of hBN are placed on top or below the hollow site of graphene, corresponds to the magnetic proximity effect of B atoms on graphene, causing the opening and closing of MGDC with a small gap size. The second structure corresponds to the structure where one of either upper or lower N atoms of hBN parallel with one C atom of graphene. This structure shows the proximity effect of Ni(111) surface state as an evanescent wave acts on C atoms. Both APC and PC states have a one-spin channel with a prominent size of mass-gapped, while the other does not. The last structure shows the MGDC is open with a significant gap size in the APC state and closed in the PC state. In this structure, the asymmetric arrangement of N atoms on different sublattices of graphene is considered. Utilizing the unique characteristics of graphene's MGDC control, which depends on the stacking configuration, a device where a controllable MGDC is tuned using mechanical motion can be proposed. A spin-mechatronics device can be realized by proposing a device that can move the upper and lower Ni(111)/hBN slabs translationally.