Integrated setup for time and spatially resolved micro-photoluminescence

We report on a setup for photoluminescence (PL) spectroscopy, allowing to perform time resolved, steady-state, and spatially resolved PL and PL imaging. Time domain information (with ≈50 ps resolution) is achieved via time-correlated single photon counting (TCSPC), while the spectral information (in the ≈1–4 eV NIR-UV energy range) is accessed through a common-path interferometer based on birefringence, with the PL spectrum being retrieved via a Fourier transform approach. The micro-PL approach allows us to measure the PL signal of micron-sized samples, such as exfoliated 2D semiconductors. Moreover, the high efficiency of signal collection and analysis allows us to resolve weak PL signals from indirect-bandgap semiconductors. We measure the time-, frequency-, and spatially resolved PL on exfoliated flakes of WSe₂, MoS₂, and WS₂ as examples to display the potential of our new apparatus.