Physics Colloquium – Dr. Joshua “Shua” Sanchez

Dr. Joshua “Shua” Sanchez, Postdoctoral Fellow, Department of Physics, MIT

Quantum Criticality and Magnetic Field-Induced Superconductivity

When electrons have strong interactions with each other, new quantum phases of matter emerge, such as magnetism, nematicity, charge order, and superconductivity. In these “Quantum Materials”, the microscopic interactions can be very difficult to probe and understand, yet they give rise to macroscopic properties that are easier to study and can be harnessed for new technologies.

In this talk, I will demonstrate how synchrotron x-ray techniques can be powerful probes to study the mysterious origin of strongly-correlated phases. I will discuss several recent projects at the Advanced Photon Source at Argonne National Laboratory, using a novel sample characterization platform that simultaneously combines x-rays, in-situ structural tuning, applied magnetic field, and electrical transport measurements. Our work yields new insights on two broad questions in high-temperature iron-based superconductors. (1) How does quantum criticality and nematicity relate to unconventional superconductivity? and (2) How can ferromagnetism and superconductivity coexist in one material, and how do they affect each other?

References:
(1) Sanchez, et al. Nature Materials 20, 1519–1524 (2021)
(2) Sanchez, et al. Science Advances 9, eadj5200 (2023)

The event flyer is available here.