Topological spintronics in a polyacetylene molecule device

Abstract

Using the Su-Schrieffer-Heeger Hamiltonian and exploiting the Green's function method in the framework of the Landauer-Büttiker formalism, the topological and spin dependent electron transport properties of a trans polyacetylene molecule are studied. It is found that molecules with the intracell single carbon-carbon bonding and the even number of monomers in their chains have two edge states and possess topological properties though their Hamiltonians do not respect the chiral symmetry. A perpendicular exchange magnetic field and two perpendicular and transverse electric fields are used to induce and manipulate the quantum spin dependent electron transport properties. The exchange field induces the spin polarization in different electron energy regions which are expanded by stronger exchange fields. Therefore this proposed device works as a perfect spin filter. The spin polarization can be manipulated by applying the perpendicular electric field and remains robust against the transverse electric field variations.

Recent Advances in the Spintronic Application of Carbon-Based Nanomaterials

“…In another study, M.A.M. Keshtan and M. Esmaeilzadeh investigated the topological and spin-dependent electron transport characteristics of a trans-polyacetylene molecule [ 68 ]. Even though their Hamiltonians do not adhere to chiral symmetry, it was discovered that molecules with intracellular single carbon–carbon bonds and an even number of monomers in their chains exhibit two edge states and contain topological features.…”