Bias-induced reconstruction of hybrid interface states in magnetic molecular junctions

Based on first-principles calculations, the bias-induced evolution of hybrid interface states in π-conjugated tricene and insulating octane magnetic molecular junctions is investigated. Obvious bias-induced splitting and energy shift of the spin-resolved hybrid interface states are observed in the two junctions. The recombination of the shifted hybrid interface states from different interfaces makes the spin polarization around the Fermi energy strongly bias dependent. The transport calculations demonstrate that in the π-conjugated tricene junction, the bias-dependent hybrid interface states work efficiently for large current, current spin polarization, and distinct tunneling magnetoresistance. But in the insulating octane junction, the spin-dependent transport via the hybrid interface states is inhibited, which is only slightly disturbed by the bias. This work reveals the phenomenon of bias-induced reconstruction of hybrid interface states in molecular spinterface devices, and the underlying role of molecular conjugated orbitals in the transport ability of hybrid interface states.

Andreev reflection spectroscopy in transition metal oxides

Here we review the literature concerning measurement of the Andreev reflection between a superconductor (S) and ferromagnet (F), with particular attention to the case where the ferromagnet is a transition metal oxide. We discuss the practicality of utilization of the current models for determination of the transport current spin polarization and examine the evidence for Andreev bound states. This article is part of the theme issue ‘Andreev bound states’.

AMPLIFICATION OF CURRENT SPIN POLARIZATION IN FERROMAGNETIC/ORGANIC SYSTEM WITH SPIN-RELATED INTERFACIAL RESISTANCES

Current spin polarization in ferromagnetic/organic system is theoretically studied based on the spin diffusion theory and Ohm's law, and the effects of the spin-related interfacial resistances on the spin-polarized injection are discussed. It is shown that the current spin polarization can be higher than the spin polarization of the ferromagnetic contact and may reach 100% at the interface by modulating the spin-related interfacial resistances. The proposed amplification scheme provides an efficient way to generate a highly spin-polarized current in organic materials because of the easy fabrication of ordered spin-related tunnel barriers at contact structures.

The Spin-Dependent Electronical Conductivity of Polarons in the Spin Polarized Organic Semiconductor

The spin-dependent electronical conductivity of polarons is studied in the spin polarized organic semiconductor .It is found that the spin dependence of the electronical conductivity is induced by the spin polarization of the organic semiconductor, for the spin polarization makes the up-spin and the down-spin polarons have different density, which generates the spin-dependent electronocal conductivity. The spin-dependent electrical conductivity can be directly affected by the match level of conductivities s0/sf at the interface of the FM/OSE. Moreover, the current spin polarization in the organic semiconductor can be strengthened by the electric-field in the low-electric-field region .