| Switchable Polarization in Mn Embedded Graphene Mazia Asghar1; Hamid Ullah1; 1RIPHAH INTERNATIONALUNINVERSITY, LAHORE CAMPUS, PAKISTAN, Lahore, Pakistan; PAPER: 439/ModellingMaterials/Regular (Oral) SCHEDULED: 12:45/Wed. 30 Nov. 2022/Andaman 1 ABSTRACT: Graphene, despite its many unique properties, is neither intrinsically polar due to inversion symmetry nor magnetic. However, based on density functional theory, we find that Mn, one of the transition metals, embedded in single or double vacancy (Mn@SV and Mn@DV) in a graphene monolayer induces a dipole moment perpendicular to the sheet, which can be switched from up to down by Mn penetration through the graphene. Such switching could be realized by an external stimulus introduced through the tip of a scanning probe microscope, as already utilized in the studies of molecular switches. We estimate the energy barriers for dipole switching, which are found to be 2.60 eV and 0.28 eV for Mn@SV and Mn@DV, respectively. However, we propose a mechanism for tuning the barrier by applying biaxial tensile strain. We find that 10% biaxial tensile strain, already experimentally achievable in graphene-like two-dimensional materials, can significantly reduce the barrier to 0.16 eV in Mn@SV. Moreover, in agreement with previous studies, we find a high magnetic moment of 3 μB for both Mn@SV and Mn@DV, promising the potential of these structures in spintronics and nanoscale electro-mechanical or memory devices. References: Polarization Switching Graphene |
