Uniaxial Stress Technique And Investigations Of Correlated Electron Systems

Uniaxial Stress Technique and Investigations of Correlated Electron Systems

This book reports on the development and application of a new uniaxial pressure apparatus that is currently generating considerable interest in the field of materials physics. The author provides practical guidelines for performing such experiments, backed up by finite element simulations. Subsequently, the book reports on two uses of the device. In the first, high pressures are used to tune to a Van Hove singularity in Sr2RuO4, while the effects on the unconventional superconductivity and the normal state properties are investigated. In the second experiment, precise and continuous strain control is used to probe symmetry breaking and novel phase formation in the vicinity of a quantum critical point in Sr3Ru2O7.

Uniaxial Stress Technique and Investigations Into Correlated Electron Systems

Manipulating Anisotropic Transport and Superconductivity by Focused Ion Beam Microstructuring

This thesis presents pioneering work in the relatively new field of focused ion beam (FIB) sculpting of single crystals to produce bespoke devices and enable the investigation of physics that cannot be studied in bulk samples. It begins with a comprehensive and didactic account of how to achieve this sculpting, revealing the ‘tricks of the trade’ of state-of-the-art FIB microstructuring. In subsequent chapters, the author presents ground-breaking results obtained from microstructures of the delafossite oxide metal PdCoO2 and the heavy fermion superconductor CeIrIn5. In these elegant, forefront experiments, a new form of directional ballistic transport in the ultra-pure delafossites is described and explained. Furthermore, a new way to spatially modulate superconductivity induced by strain is demonstrated with electrical transport measurements that agree well with predictions based on thermoelastic finite element simulations.