ICE1 2014 Workshop “Información Cuántca en España-1” - Zaragoza, 2014
A molecular approach to spin qubits: decoherence and organisation in Single-Ion-Magnets
Universitat de València, ICMol, Spain
Magnetic molecules based on rare earth ions are promising hardware to perform theoretical and experimental studies with the final goal of achieving coherent spin control. In this context, we employ as theoretical tools the home-made programs MAGPACK and SIMPRE. Experimentally, we rely mostly on magnetometry for characterization -complemented when available by spectroscopic techniques- and pulsed-Electronic Paramagntic Resonance for the coherent manipulation. In a recent experimental study, it was possible to increase the number of coherent rotations tenfold through matching the Rabi frequency with the frequency of the proton for the polyoxometalate single ion magnet [GdW30P5O110]14-. We have been recently able to understand the magnetic anisotropy of lanthanoid complexes using an effective point-charge model. Building upon this understanding, we are now proposing a new setup for the electrical control of spin qubits embodied by mononuclear lanthanide complexes, via the change in the extradiagonal parameters of the crystal field Hamiltonian. We rationalize the expected results with the help of ab initio calculations and an effective point charge model. We also propose a Quantum Error Correction experiment inspired by the Shor code using a trinuclear lanthanide complex in an ENDOR setup. We detail how the combined electron-nuclear spin manifold in this system can be thought of as equivalent to the 9 qubits as required by Shor's code. Finally, we recently achieved the spatially regular organisation of three different spin qubits, reminiscent of Lloyd's “global control” scheme for quantum computing.
 J. J. Baldoví, S. Cardona-Serra, J. M. Clemente-Juan, E. Coronado, A. Gaita-Ariño and A. Palii, J. Comput. Chem., 2013, 34, 1961-1967
 J. J. Baldoví, S. Cardona-Serra, J. M. Clemente-Juan, E. Coronado, A. Gaita-Ariño and H. Prima,, Chem. Comm., 2013, 49, 8922- 8924, arxiv:1308.5839
 J. J. Baldoví et al, submitted
 J. J. Baldoví et al, Chem. Eur. J., 2014 (DOI: 10.1002/chem.201402255)