60699 20190709135444.0 doi 10.1103/PhysRevB.95.064423 sideral 98156 ART-2017-98156 eng Jenkins, M.D. Coherent manipulation of three-qubit states in a molecular single-ion magnet 2017 Access copy available to the general public Unrestricted We study the quantum spin dynamics of nearly isotropic Gd3+ ions entrapped in polyoxometalate molecules and diluted in crystals of a diamagnetic Y3+ derivative. The full energy-level spectrum and the orientations of the magnetic anisotropy axes have been determined by means of continuous-wave electron paramagnetic resonance experiments, using X-band (9-10 GHz) cavities and on-chip superconducting waveguides and 1.5-GHz resonators. The results show that seven allowed transitions between the 2S+1 spin states can be separately addressed. Spin coherence T2 and spin-lattice relaxation T1 rates have been measured for each of these transitions in properly oriented single crystals. The results suggest that quantum spin coherence is limited by residual dipolar interactions with neighbor electronic spins. Coherent Rabi oscillations have been observed for all transitions. The Rabi frequencies increase with microwave power and agree quantitatively with predictions based on the spin Hamiltonian of the molecular spin. We argue that the spin states of each Gd3+ ion can be mapped onto the states of three addressable qubits (or, alternatively, of a d=8-level "qudit"), for which the seven allowed transitions form a universal set of operations. Within this scheme, one of the coherent oscillations observed experimentally provides an implementation of a controlled-controlled-NOT (or Toffoli) three-qubit gate. info:eu-repo/grantAgreement/ES/DGA/E98-MOLCHIP info:eu-repo/grantAgreement/ES/MINECO/CTQ2014-52758-P info:eu-repo/grantAgreement/ES/MINECO/CTQ2015-64486-R info:eu-repo/grantAgreement/ES/MINECO/FIS2015-70856-P info:eu-repo/grantAgreement/ES/MINECO/MAT2014-56143-R info:eu-repo/grantAgreement/ES/MINECO-FEDER/MAT2015-68204-R info:eu-repo/semantics/openAccess by-nc-nd http://creativecommons.org/licenses/by-nc-nd/3.0/es/ 1.604 2017 Electronic, Optical and Magnetic Materials 2017 Q1 Condensed Matter Physics 2017 Q1 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Duan, Y. Diosdado, B. García-Ripoll, J.J. Gaita-Ariño, A. Giménez-Saiz, C. (orcid)0000-0003-3449-4929 Alonso, P.J. Universidad de Zaragoza Coronado, E. (orcid)0000-0001-6284-0521 Luis, F. Universidad de Zaragoza 2003 395 Universidad de Zaragoza Dpto. Física Materia Condensa. Área Física Materia Condensada 95, 6 (2017), 064423 [8 pp.] Phys. Rev. B, Condens. matter mater. phys. Physical Review B. Condensed Matter and Materials Physics 1098-0121 2689277 http://zaguan.unizar.es/record/60699/files/texto_completo.pdf Versión publicada 134996 http://zaguan.unizar.es/record/60699/files/texto_completo.jpg?subformat=icon icon Versión publicada oai:zaguan.unizar.es:60699 articulos driver 2019-07-09-11:37:39 ARTICLE