Quantum complexity in simple materials
Two-dimensional(2D) materials have received widespread attention over the past 20 years due to their remarkable physical, mechanical, and chemical properties, and our ability to integrate them into devices. In this seminar, I will discuss a new approach for realizing long-sought electronic structures of geometrically frustrated lattice models (e.g., kagome and pyrochlore), by “decorating”un-frustrated, primitive lattices with a particular set of atomic orbitals. In the process, we identify the vdW intermetallic compound Pd5AlI2as the first material to realize the electronic structure of the 2D Lieb lattice– featuring Dirac-like bands intersected by a flat band – persisting in ambient conditions down to the monolayer limit. I will discuss how this unique electronic structure gives rise to compact localized states and bound states in continuum (BICs), which could provide a platform for lossless and topologically protected electronic processes. I will then detail our recent synthesis of CeSiI, the first van der Waals (vdW) metal with a heavy fermion ground state. Conceptually, our synthetic design takes a traditional 3D intermetallic structure and slices it into atomically-thin vdW sheets by incorporating iodine into the structure. The resulting material is cleavable and effectively electronically 2D.