An Integrated Quantum Material Testbed with Multi-Resolution Photoemission Spectroscopy

TL;DR

This paper introduces a versatile multi-resolution photoemission spectroscopy setup capable of probing quantum materials with high energy, momentum, space, and time resolution, integrating multiple techniques and a growth system for comprehensive material analysis.

Contribution

The work presents the first integrated photoemission setup combining ARPES, trARPES, and $mbda$ARPES with high resolution and a growth system, enabling advanced quantum material characterization.

Findings

Achieved energy resolution < 4 meV, time resolution < 35 fs, spatial resolution ~10 μm.

Demonstrated the system's capabilities on FeSe/SrTiO$_3$ and MnBi$_4$Te$_7$ samples.

Shortest time resolution among solid-state trARPES setups.

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 micron-scale spatially resolved ARPES ($\mu$ARPES). It provides a first-time all-in-one solution to achieve an energy resolution $< 4$ meV, a time resolution $< 35$ fs, and a spatial resolution $\sim 10$ $\mu$m 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/SrTiO$_3$ thin films and MnBi$_4$Te$_7$ magnetic topological insulators.