91福利

Speaker: Dr Chris Wedge, Physical & Theoretical Chemistry Laboratory, University of Oxford

The proposal that molecular nanomagnets could be used as solid state qubits has stimulated great interest in these systems during the past decade. It has often been stated that the flexibility in their synthesis should allow engineering of molecular nanomagnet systems with desirable properties, and indeed individual Cr₇Ni molecular nanomagnets have been both linked to provide coupled qubits and deposited onto surfaces in preparation for single molecule manipulation. It will be shown that the electron spin phase memory time, the most important property of a molecular nanomagnet from the perspective of quantum information processing, can be improved dramatically by chemically engineering the molecular structure to optimise the environment of the spin. By systematically varying each structural component of the Cr₇Ni molecular nanomagnet the sources of decoherence are identified. The optimal structure exhibits a phase memory time exceeding 15 μs

Speaker: Dr Amy Webber, The Clarendon Laboratory, University of Oxford

Abstract:

I will address a more fundamental concern of research by asking why this chosen field is so deserving of our attention and effort. Using examples from my own work in solid-state NMR and EPR, I will highlight how continuing advancements have allowed Magnetic Resonance to grow into an incredibly powerful experimental technique which is able to answer important research questions across all disciplines of science.

Speaker: Dr Stephen Sproules, School of Chemistry and Photon Science Institute, The University of Manchester

Abstract:

The crystal structure of [Re(pdt)₃] (pdt = 1,2-diphenyl-1,2-dithiolate) was the first example of a trigonal prismatic coordination complex. As such, it was extensively studied by spectroscopic and theoretical techniques to identify the electronic reasons for its unusual geometry. Having an S = ¹/₂ ground state made it accessible to EPR spectroscopy, however, the spectrum is complicated and no attempts were initiated to explain these observations. Presented here is the correct interpretation of the spectrum that includes a colossal quadrupole coupling of the ^183,185Re nuclei. This afforded an unambiguous electronic structure description of the neutral tris(dithiolene)rhenium compound. The result allowed assignment of the other three members of the electron transfer series interconnected by reversible one-electron steps by S K-edge X-ray absorption spectroscopy, and complemented by DFT calculations.

The intriguing physical characteristics displayed by transition metal dithiolenes stems from the intrinsic redox activity of the ligand. This trait is exploited in the design of novel molecular spin qubits where traditional role of the organic and inorganic components is reversed. The electron spin is anchored on ligands linked by metal ions to form prototypical two- and three-qubit gates for quantum computing.

Prof. Ángel S. Sanz Ortiz,

Instituto de Física Fundamental (CSIC), Madrid