An integrated quantum material testbed with multi-resolution photoemission spectroscopy

Abstract

We present the development of a multi-resolution photoemission spectroscopy (MRPES) setup, which probes quantum materials in energy, momentum, space, and time. This versatile setup integrates three light sources in one photoemission setup and can conveniently switch between traditional angle-resolved photoemission spectroscopy (ARPES), time-resolved ARPES (trARPES), and micrometer-scale spatially resolved ARPES. It provides a first-time all-in-one solution to achieve an energy resolution of <4 meV, a time resolution of <35 fs, and a spatial resolution of ∼10 μm in photoemission spectroscopy. Remarkably, we obtain the shortest time resolution among the trARPES setups using solid-state nonlinear crystals for frequency upconversion. Furthermore, this MRPES setup is integrated with a shadow-mask assisted molecular beam epitaxy system, which transforms the traditional photoemission spectroscopy into a quantum device characterization instrument. We demonstrate the functionalities of this novel quantum material testbed using FeSe/SrTiO3 thin films and MnBi4Te7 magnetic topological insulators.