Spin filtering and switching action in a diamond network with magnetic-nonmagnetic atomic distribution

TL;DR

This paper models a diamond-shaped quantum network with magnetic and non-magnetic atoms, demonstrating controllable spin filtering and switching effects driven by magnetic flux and magnetic moment orientations, with potential applications in spintronic devices.

Contribution

It introduces a simple quantum network model showing tunable spin filtering and flux-controlled switching, including effects of disorder on spin transport.

Findings

Magnetic flux induces a switch-like control over spin transmission.

Magnetic moment orientations influence energy band engineering for spin channels.

Disorder can lead to spin filtering by blocking one spin channel.

Abstract

We propose a simple model quantum network consisting of diamond-shaped plaquettes with deterministic distribution of magnetic and non-magnetic atoms in presence of a uniform external magnetic flux in each plaquette and predict that such a simple model can be a prospective candidate for spin filter as well as flux driven spintronic switch. The orientations and the amplitudes of the substrate magnetic moments play a crucial role in the energy band engineering of the two spin channels which essentially gives us a control over the spin transmission leading to a spin filtering effect. The externally tunable magnetic flux plays an important role in inducing a switch on-switch off effect for both the spin states indicating the behavior like a spintronic switch. Even a correlated disorder configuration in the on-site potentials and in the magnetic moments may lead to disorder-induced spin filtering phenomenon where one of the spin channel gets entirely blocked leaving the other one transmitting over the entire allowed energy regime. All these features are established by evaluating the density of states and the two terminal transmission probabilities using the transfer-matrix formalism within a tight-binding framework. Experimental realization of our theoretical study may be helpful in designing new spintronic devices.