Spin-Polarized Transport Through Devices of Er Single-Ion Magnets and Its Derivatives

We will study the spin-polarized transport through devices of single-ion magnets. A device consisted of the scanning tunneling microscopy (STM) Co tip, the single-ion magnet (Cp*) Ln (COT) (Cp* represents pentamethyl pentacadiene; Ln represents ErIII, DyIII, HoIII; COT stands for cyclooctatetraene), and the Au(111) substrate is proposed. We calculate the current curve for the parallel and anti-parallel configurations for the device of Er single-ion magnet, and find that the tunnel magnetoresistance (TMR) changes with bias − 34~24%, which indicates it is promising for the application in magnetic storage. After comparing the currents through devices of (Cp*) Ln (COT) single-ion magnets, we find that Er single-ion magnet has a better rectifying character than Dy and Ho single-ion magnet, but Ho single-ion magnet has an obvious negative differential conductance. By analysis of their transmission spectrums, these properties are well explained. The spin-polarized transport for the derivatives of Er single-ion magnets is also investigated; we find that they have better rectification and negative differential conductance features, and have potential application on multifunctional molecular devices.