Momentum microscopy and its applications

Experimental tools lie at the heart of discovering science. The ability to develop transformative tools that enable unprecedented insight into the physical and chemical properties of materials will significantly advance many fields of scientific research. The visionary aim of probing and visualizing the quantum degree of freedom of materials requires a comprehensive access to orbital symmetries, spin, and dynamics of quantum states across large regions of the momentum space. Momentum microscopy stands as the most advanced experimental technique for probing the electronic structure of materials, uniquely unifying spin, orbital, time, spatial, momentum, and energy information in a single experiment. In this Perspective, we provide an overview of momentum microscopy and its applications. We review state-of-the-art all-in-one photoemission experiments and highlight recent advances enabled by momentum microscopy. We conclude this Perspective with the exciting future directions currently developing in the field.