The device model employed to investigate the transport properties of 6ZGNRH is illustrated in Figure , where 6 defines the number of C atoms along the width of ZGNR and H represents the fact that the dangling bonds in 6ZGNR are passivated with H atoms. The device comprises of total 13 unit cells for 6ZGNRH and is divided into three regions: left electrode, right electrode, and scattering region as shown in Figure . Out of the total unit cells, 4 unit cells are used for semi-infinite left and right electrodes, while the remaining 9 unit cells are assigned as the scattering region for 6ZGNR. To study the spin-polarized electron transmission through ZGNRs, TMM radical is deposited in different configurations on the scattering region of 6ZGNRH.