Physics and Astronomy PhD (Condensed Matter Physics specialism)

The research carried out by the Condensed Matter Physics Research Group probes fundamental and applied aspects of quantum effects in solids, superconducting qubits and novel superconducting and magnetic materials. 

Our key research areas are: flux lines in high temperature and novel superconductors; superconducting qubits; quantum effects in solids; and biophysics applications.

The research carried out by the Condensed Matter Physics Research Group probes fundamental and applied aspects of quantum effects in solids, superconducting qubits and novel superconducting and magnetic materials.

Research areas

Flux lines in high temperature and novel superconductors

The ‘condensate’ of Cooper pairs in a superconductor means that magnetic fields pass through in the form of quantised flux lines, each containing one quantum of flux associated with circulating supercurrents. The structure and dynamics of magnetic flux lines in superconductors, which may form a lattice, liquid or a 'glass' are studied experimentally by small-angle neutron diffraction and muon spin rotation, using international facilities.

The flux lattice structure tells us about fundamental interactions inside superconductors. In addition to “cuprate” high temperature superconductors, there is a wide range of metals with novel electrical and magnetic properties arising from strong electron correlations. They include Sr2RuO4 which is believed to be a p-wave superconductor, in which the electrons are paired with parallel spin, as opposed to the opposite spins of conventional and cuprate superconductors. We are also investigating the properties of CeCoIn5, which is a “Pauli-limited” “heavy fermion” superconductor, in which the superconductivity in high magnetic fields is suppressed by the magnetic effects on the electron spin, instead of the usual diamagnetism. The properties of these novel materials are studied using muon and neutron measurements at temperatures down to 50 mK in fields as high as 11 T.

Professor Ted Forgan and Dr Elizabeth Blackburn

Superconducting Qubits

The study of Josephson tunnel junctions and device applications includes the evaluation of superconducting 'qubit' structures, which may form the building blocks of quantum computers. These are being made from both conventional and high temperature superconductors, and allow us to observe the quantum behaviour of a “macroscopic” object. Such measurements use temperatures close to absolute zero obtained with dilution refrigerators or adiabatic demagnetisation, plus clever design to avoid the disturbing influence of electrical noise.

Dr Chris Muirhead, Dr Mark Colclough and Dr Edward Tarte

Quantum effects in solids

We are interested in making measurements on a wide range of systems using big international facilities such as synchrotrons and neutron sources. With international and Birmingham collaborators, we are currently investigating the dynamics of solid helium, for which the structure and atomic motion is controlled by quantum mechanics, magnetic thin film structures and devices, unconventional superconductors and magnetic materials.

Dr Elizabeth Blackburn

Biophysics applications

We are using magnetic measurements in an interdisciplinary project using SQUIDS and minute electrical connections for observation of living biological systems

Dr Mark Colclough and Dr Edward Tarte