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Molecular engineering of antiferromagnetic rings for quantum computation

F. Troiani·A. Ghirri·M. Affronte·S. Carretta·P. Santini·G. Amoretti·S. Piligkos·G. Timco·R. E. P. Winpenny
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Abstract

The substitution of one metal ion in a Cr-based molecular ring with dominant antiferromagnetic couplings allows to engineer its level structure and ground-state degeneracy. Here we characterize a Cr7Ni molecular ring by means of low-temperature specific-heat and torque-magnetometry measurements, thus determining the microscopic parameters of the corresponding spin Hamiltonian. The energy spectrum and the suppression of the leakage-inducing S-mixing render the Cr7Ni molecule a suitable candidate for the qubit implementation, as further substantiated by our quantum-gate simulations.

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F. Troiani, A. Ghirri, M. Affronte, S. Carretta, P. Santini, G. Amoretti, S. Piligkos, G. Timco, R. E. P. Winpenny. 2005-04-25. Molecular engineering of antiferromagnetic rings for quantum computation. https://doi.org/10.1103/physrevlett.94.207208

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