Magnetic Molecules as Spin Qubits

The encoding of qubits in spins has been proposed in many contexts, such as Nuclear Magnetic Resonance, impurity centers in semiconductors, or quantum dots in a variety of different materials. Electron spins in solid-state systems are promising candidate qubits because of their relative decoupling from the environment and integration in a solid-state matrix. Besides single-electron spins, collective degrees of freedom resulting from coupled electron spins in molecular nanomagnets can be used to encode qubits. These have attracted significant interest for the large amount of opportunities, still partly unexplored, offered by chemical engineering of the intramolecular structure, which permits one to design and synthesize nanomagnets fitting specific requisites. Here we present an overview of the field, and in particular, we illustrate how a suitable hierarchy of interactions can be exploited to mimic switchable two-qubit interactions.