Quantum coherence driven magnetic ordering in biased three level coordination compounds

TL;DR

This paper demonstrates how quantum coherence influences magnetic ordering in a biased three-level molecular system, enabling electrical control of spin states for quantum device applications.

Contribution

It reveals that bias and gate voltages can switch the magnetic states of a molecular trimer, highlighting the role of quantum coherence in electrically tunable spin arrangements.

Findings

Bias and gate voltages induce ferromagnetic or frustrated spin states.

Electrical control allows switching between different magnetic configurations.

Quantum coherence affects spin ordering and electronic interference.

Abstract

Novel understanding of the recent nanomagnet tailoring experiments and the possibility to further unveil the mechanisms by which the magnetic interactions arise in an atom by atom fashion covers importance as the demand for spin qubit and quantum state detection architectures increases. Here, we address the spin states of a molecular trimer comprising three localized spin moments embedded in a metallic tunnel junction and show that the pair spin interactions can be engineered through the electronic structure of the molecular trimer. We show that bias and gate voltages induce either a completely ferromagnetic state of the localized moments or a spin frustrated state with different stabilities, and that switching between these states is possible on demand by electrical control. The role of quantum coherence in the molecular trimer is discussed with regards to the spin ordering as well as the interplay among electronic interference and induced dephasing by the metallic leads. This work sets foundations for more robust all electrically controlled spin architectures usable in quantum engineering systems and serves as a test bench for exploring unresolved questions in magnetic ordering and symmetry.