Application of the uniaxial pressure technique in studying superconductors

Abstract

<p indent=0mm>Because of the rapid development of the uniaxial pressure device in recent years, the uniaxial pressure or strain technique has been increasingly applied to study unconventional superconductors. The physical properties of a sample will change with the uniaxial strain along a particular lattice axis, providing us with important information regarding superconductivity and other characteristics. When compared with hydrostatic pressure measurement, changes in physical properties with the uniaxial pressure are mainly associated with symmetry, making this methodology particularly suitable for studying the symmetry-related properties of a system such as the electronic nematic phase with rotational symmetry breaking. Furthermore, the uniaxial pressure technique can be used to study the superconducting properties. In this review, we will briefly introduce some typical uniaxial pressure and uniaxial strain devices and techniques and their applications on iron-based superconductors as well as other superconductors. The uniaxial pressure technique exhibits some unique advantages with respect to the study of electronic nematicity, superconductivity, and some other competing orders. With further development, the uniaxial pressure technique is expected to play increasingly important roles in the study of superconductors and other strongly correlated systems.