Investigation of Nanoscale properties of Topological Weyl semimetals

ended

Weyl semimetals are a recently-discovered class of topological quantum materials predicting unexpected and extraordinary transport properties. Their electronic band structure features valence and conduction bands crossing in paired Weyl nodes with opposite chiralities. In such systems the conduction electrons behave as topologically-protected massless quasiparticles with an ultra-high carrier mobility and well-defined spin-momentum locking configurations. The unique combination of these properties has attracted the attention of the scientific community that is currently striving to unveil the complex physics underlying Weyl semimetals. Besides, from a technological perspective, Weyl semimetals are expected to provide an ideal platform to test novel device functionalities in the areas of information technology, energy conversion and sensing. Nonetheless, being a newborn field in science, so far the research activities have focused on Weyl semimetals in the form of bulk single crystalline materials. The main objectives of this action are to comprehensively investigate the yet-unexplored properties of Weyl semimetals at the nanoscale and to define possible integration routes for new-generation microelectronic devices. For this purpose, epitaxial thin films of Weyl semimetals will be used as referent systems to probe the influence of different control parameters (e.g. by substrate-induced strain, film thickness, interfaces, external electric and/or magnetic fields) on their structural and electronic properties. Eventually, the potential impact of Weyl semimetals in current microelectronic schemes will be evaluated by designing prototypes based on field-effect and magnetic heterostructures. In this context, the state-of-the-art facilities and the well-established expertise in the fabrication and characterization of complex nanostructures present at IBM Research Zurich offer an ideal environment to tackle the challenge of studying Weyl semimetals at low-dimensionality.