We are pleased to inform you that the seminar will be held as follows.
Please see below for details. We look forward to your participation.
Speaker:Prof. Young-June Kim
Affiliation:Department of Physics, The University of Toronto
Title:Uniaxial Strain as a tool for controlling High-Temperature Superconductivity
Date and Time: March 12 (Thu) 11 am to noon (JST)
Place:Rm 206, Faculty of Science Building No.1, Hongo campus
Zoom: https://us02web.zoom.us/j/81218549862?pwd=mDQCe3aGMb1A3XWxoodab8dEEfvgYa.1
Meeting ID: 812 1854 9862
Passcode: 128641
Abstract:
A recently developed uniaxial strain device enables continuous in-situ control of lattice degree of freedom, which, in turn, could tune electronic phases, and has gained significant attention in recent years as a powerful tool for studying quantum materials. Competition between electronic and lattice degrees of freedom in high-temperature cuprate superconductors makes them an excellent candidate for this experimental tool. We will discuss two examples that show very different responses to uniaxial strain. First, when moderate uniaxial strain is applied to a system near a structural instability, it leads to non-trivial phase separation, as demonstrated by studies of La2−xBaxCuO4 near the low-temperature tetragonal (LTT) and low-temperature orthorhombic (LTO) phase transitions. Secondly, application of uniaxial strain in a tetragonal structure can lead to a large shift in superconducting transition temperature Tc in La1.6-xNd0.4SrxCuO4. The observed Tc shift is strongly doping-dependent and exhibits a striking in-plane anisotropy. Most surprisingly, we found a non-monotonic, V-shaped, Tc response to the strain. These studies illustrate the rich physics revealed by applying moderate uniaxial strain to quantum materials.

