Theme 3 colloquium: "Controlling and imaging emergent states in quantum materials" (Lecture)
- Tuesday 19 March 2019Add to my calendar
- from 16:00
prof. Peter Wahl (School of Physics and Astronomy, University of St Andrews, UK),
Quantum materials host many properties, which are highly desirable for technological applications, yet our lack of understanding of their physics often prevents them from being exploited. A delicate balance between different competing interactions results in emergent phenomena such as magnetic order and superconductivity. Understanding the interactions which govern these phases is believed to be key to unravelling their enigmatic properties and making them amenable for applications. Here, I will discuss how imaging of these emergent phases by spin-polarized Scanning Tunneling Microscopy in vector magnetic fields combined with spectroscopy can be used to establish a better understanding of the underlying physics.
fig.: Atomic scale image of the magnetic order in the parent compound Fe1+δTe of the iron chalcogenide superconductors. Red and Blue indicate areas where the magnetization points in opposite directions.
In my talk, I will show how we can control the emergent magnetic order in Fe1+δTe (fig. 1) through manipulation of the surface composition, and how the results can be used to understand the dominant magnetic interactions and their impact on the magnetic order. In the second part, I will address the interplay between magnetic order and superconductivity in the iron chalcogenide superconductors.