Abstract

When electrons are forced to interact strongly with each other, some of the most exotic electronic phases and novel quasiparticles can emerge. A key approach to force electrons to strongly interact with one another is to confine them to energy bands with no momentum dispersion, i.e. flat bands. Flat bands can be realized in two-dimensional materials in a high magnetic field or in newly discovered moiré materials in which quantum interference can give rise to flat energy bands. The journey of exploring old and new flat bands, using high resolution quantum microscopy, has taken us from confirming some of the earliest predictions for correlated phases of matter (such as formation of Wigner crystal), to new approaches to probe novel quantum phases that host exotic quasiparticles that are neither bosons or fermions. These quantum phases may play a key role in the future of quantum computing by providing an approach to build topological qubits. I’ll describe how a combination of imaging electronic states on the nanoscale and building structures from two-dimensional materials and their stacks may make building such qubits possible.