Atomic-scale dynamics & two-dimensional superconductivity: probing molecular properties, ultrathin epitaxial superconductors and AC-driven dynamics with scanning probe techniques

Abstract

The laws of quantum mechanics play an important role in materials at the level of individual atoms. Quantum effects can be revealed using a scanning tunneling microscope (STM). Indeed, the extremely high resolution of an STM can visualise individual atoms and measure both electronic and magnetic properties of materials. In this PhD thesis, the STM technique was further developed to also measure dynamic properties at very low temperatures, only 30 mK above absolute zero. This allows a single individual molecule to be examined on a surface to learn more about its exact structure, dynamics, and magnetism. This thesis also investigates how a superconducting material, namely aluminium, changes as the material becomes increasingly thin, down to thicknesses of just four atomic layers. It turns out that the superconductivity in these ultra-thin layers is three times stronger and very robust against parallel magnetic fields. New insights into atomic magnets and superconductors support the development of the next generation of quantum computers.