A family of spin-switching, inhomogeneous Hubbard chains

• This paper proposes a family of finite, inhomogeneous Hubbard chains with tunable spin-switching properties.
• Spin-switching occurs by external magnetic field and electron addition therefore enabling single electron detection via a change in the spin-structure.
• The physics of these systems can be mapped to a coupled quantum dot array.
• The underlying quantum mechanisms may be applicable in the future design of tunable, high-density reading and storage devices.

A family of spin-switching, inhomogeneous, Hubbard-type systems is proposed consisting of finite chains of nonmagnetic N-atoms separated by a magnetic M-atom spacer. Due to the extended N-atom region, multiple spin-switching events can be activated upon application of an external magnetic field and as a function of the electron filling. Varying the external magnetic field strength enables spin-switching to be triggered by the addition of a single electron. Extended Coulomb interactions are used to produce a greater range of spin-switching signals. The potential to tune the spin-switching as a function of the N/M atom ratio and model parameterization is also demonstrated.