Unconventional phases under extreme conditions
External pressure is an ideal tool to tune deliberately materials in a clean and well-controlled way. We use hydrostatic as well as uniaxial pressure experiments to gain a better understanding of unconventional superconductivity and, more generally, to study novel quantum states of matter. In strongly correlated 4f and 5f-electron metals, for example, competing energy scales can be readily tuned by external pressure to reach a zero temperature magnetic instability, where novel unconventional quantum phases emerge in many cases. With growing interest, we investigate topological materials, including Weyl semimetals and noncollinear magnets.
In some cases, a smart combination of chemical substitution, magnetic field, and external pressure might lead to deeper insights and understanding. Even though, pressure allows tuning easily the properties of a material, the study of the physical properties becomes more challenging due to the particular restrictions posed by the high-pressure equipment. What remains essential, though, is to find and develop techniques, which allow investigating the thermodynamic, magnetic, transport, but also structural and microscopic properties of materials as complete as possible under external pressure. This is challenging task, requiring a constant effort in developing new and improving already existing experimental setups, driven by newly emerging physical questions.
Our recent work can be found here.