QTM · The Quantum Twisting Microscope - revolutionizing quantum matter imaging

In this work, we propose to build a radically new type of scanning probe microscope – the Quantum Twisting Microscope (QTM) – that will be the first capable of performing local quantum interference measurements at a twistable interface between two quantum materials. The concept, already established in preliminary experiments, is based on a unique tip made of an atomically-thin two-dimensional material. This tip allows electrons to coherently tunnel into a sample at many locations at once, making it a scanning electronic interferometer. With an extra twist degree of freedom, our microscope becomes a momentum-resolving local probe, providing powerful new ways to study the energy dispersions of interacting electrons in quantum materials. The same microscope, working in a second modality, will be the-first-of-its-kind platform for cryogenic assembly of interfaces between various van der Waals materials with full in-situ control over their twist angle. Finally, in a third modality, the QTM will make a dramatic jump, by two orders of magnitude, in the spatial resolution of electrostatic imaging. This will open a new world of interacting electron phenomena that were so far inaccessible to direct visualization. We have recently built a preliminary room temperature version of this microscope, and already observed striking quantum interference and promising results on all three fronts. By taking this new microscope to cryogenic temperatures, we expect to make multiple discoveries on a variety of fundamental questions in interacting quantum matter.