Charge and spin transport properties of Mo2X2(X= Fe,Co,Ni) molecular contacts

Abstract

We present a first-principles study of the electronic and transport properties of linear clusters Mo 2 X 2 (X = Fe,Co,Ni), formed by two X atoms separated by a nearly nonmagnetic Mo dimer, connected to gold electrodes. Density functional theory, as implemented in the SIESTA code with the generalized gradient approximation, is used to determine the spin-polarized electronic structure of the molecular contact for relaxed distances. We show that the Mo 2 X 2 clusters anchored to the gold electrodes have two different magnetic states, corresponding to the spin isomers found in the freestanding environment, one of which has parallel magnetic coupling between the X atoms across the Mo dimer and another that has antiparallel coupling. The transmission coefficients, current-voltage characteristics, and conductivity are then computed with the SMEAGOL code for the two magnetic states. We show that this system presents spin-filtering properties and magnetoresistance driven by the magnetic state of the molecular contact.

A new magnetic superatom: Cr@Zn17

“…A magnetic bistability of the same kind was found by Garcı ´a-Fuente et al in the clusters Mo 2 X 2 (X = Fe, Co, Ni), formed by two X atoms separated by a nearly nonmagnetic Mo dimer. 24 These authors found that when some of those clusters form a contact between gold electrodes, the system presents spin filtering properties and magnetorresistance driven by the magnetic state of the molecular contact. Since an external magnetic field is a way to induce a change in the magnetic state of the contact, they could also act as field sensors depending on the spin-dependence of their electronic transport properties.…”

Electronic and magnetic properties ofConMomnanoclusters from density functional calculations (n+m=xand 2Liebing1, Martín2, Trepte3 et al. 2015Phys. Rev. B

“…There are reports of a very large magnetic anisotropy for the Co-dimer 2-4 making them interesting for possible applications in future storage devices for example in combination with hexagonal carbon rings 5 . It has also been shown that Mo 2 X 2 (X = Fe,Co,Ni) clusters are able to act as a spin-filter 6 . Garcia-Fuente et al 7 computed free-standing Mo 4−x Fe x clusters and came to the conclusion that they are good candidates for molecular electronic devices.…”

Electronic and magnetic properties of Co_n Mo_m nanoclusters with n+m = x and 2<=x<=6 atoms from DFT calculations

“…There are reports of a very large magnetic anisotropy for the Co-dimer 2-4 making them very interesting for possible applications in future storage devices for example in combination with hexagonal carbon rings 5 . It has also been shown that Mo 2 X 2 (X = Fe,Co,Ni) are able act as a spin-filter 6 . Garcia-Fuente et al 7 computed free-standing Mo 4−x Fe x clusters and came to the conclusion that they are good candidates for molecular electronic devices.…”