Tetrameric Ln₂Fe₂ Complexes (Ln = La, Tb) as Models of Coupled Molecular Spin Qubits

Shubham Bisht, Michael Shatruk

Florida State University

In recent years, several systems have been proposed as candidate qubits, the fundamental units of quantum information processing.¹ Among them, magnetic molecules are especially appealing from the chemistry perspective, due to the advantage of high synthetic and spin-state tunability.² While several promising molecular qubits, with relatively long spin decoherence times, have been reported, a substantial challenge remains to connect them into organized structures, where the coupling between the qubits can be manipulated.^3,4 As an initial step toward this goal, we employ an S = 1/2 building block, (PPh₃Me)[TpFe(CN)₃] (Tp = tris(1-pyrazolyl)borate), in which three cyanides can be used as bridges to link these qubit candidates into larger architectures. Thus, reactions between (PPh₃Me)[TpFe(CN)₃] and Ln(^tBu₂qsal)₂I (Ln = La, Tb; ^tBu₂qsal = 2,4-di(tert-butyl)-6-((quinoline-8-ylimino)methyl)phenolate) afforded tetranuclear complexes {[Ln(^tBu₂qsal)₂]₂[TpFe(CN)₃]₂} (Ln₂Fe₂) that incorporate two qubit centers. In this contribution, we report structural, electronic, and magnetic properties of these clusters and discuss further steps to implement qubit assemblies with controllable linkers.

References:

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