Two-dimensional electronic spectroscopy

Two-dimensional electronic spectroscopy (2DES) is a popular technique that can track ultrafast coherent and incoherent processes in real time. Since its development in the late 1990s, 2DES has become a powerful tool for investigating ultrafast dynamics in a range of systems, including nanomaterials and optoelectronic devices. This Primer explains the underlying physical principles of 2DES and how it can be applied to study dynamic photophysical processes. The article discusses how to collect, process and analyse data, with a summary of currently available experimental configurations. Common issues and challenges are considered, focusing on the limitations and reproducibility of the technique, finishing with an exploration of potential future advances and applications.