Quantum spins in molecules

Molecules define the smallest scale for engineering objects to perform particular functions. This is also the scale on which quantum properties dominate the behaviour. This project will explore several experimental approaches to harnessing molecules (and in particular their spins) as the basic components of molecular electronic and quantum devices. The short-term impact will be academic, generating new basic science results and experimental methodologies. In the longer term, our new approaches may offer routes to commercially viable molecular device technologies.Aims and Objectives: 1. Use pulsed electron spin resonance to: (a) characterise and help optimise spin coherence times in molecular spin systems; (b) investigate inter-spin interactions in multi-spin molecules and optimise for mediating multi-qubit quantum logic operations; (c) perform a two-qubit entangling operation and verify the result using density matrix tomography; (d) investigate the dependence of molecular spin Hamiltonian parameters on externally-applied electric fields and determine whether electric fields can be used to manipulate molecular spin qubits. 2. Participate in EPSRC project EP/P000479/1 "Molecular assembly of spintronic circuits with DNA": (a) participate in design of molecular devices (to be assembled by others project participants); (b) use cleanroom-based nanolithography techniques to make electrical contact to assembled molecular devices; (c) perform electrical transport experiments on the contacted molecular devices at low temperatures and at high magnetic fields. Novelty of the research methodology: Pulsed electron spin resonance (underpinning objective 1) is an established methodology for probing the properties of magnetic molecular systems. Investigating intra-molecular interactions that could propagate multi-qubit quantum gates uses established pulse sequences in novel ways. Performing a two-qubit gate and its verification will be highly novel. Measuring electric field sensitivity of Hamiltonian parameters is an established technique, but applying it to spin qubits is highly novel. The methodology underpinning objective 2 is entirely novel; establishing the use of DNA to assemble molecular electronic devices is a completely new direction for this field of research.

Alignment to EPSRC's strategies and research areas: This project falls within the following EPSRC research areas: Physical sciences (biophysics and soft matter physics, condensed matter: electronic structure, condensed matter: magnetism and magnetic materials); Quantum technologies; Manufacturing the future.