2025/09/15 by Hinkle, Alex, Tsao, Chieh, Duell, Adam +1 · 1 citation
#FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci)
paper · doi:10.48550/arxiv.2509.12461
Lead-halide perovskite quantum dots (PQDs) are established quantum emitters with potential for entangled photon-pair generation via multiexciton cascades. However, the energetics and dynamics of many-body excitations remain poorly understood. Here, we perform time- and frequency-resolved photon-correlation spectroscopy of single CsPbBr\textsubscript3 PQDs at low temperatures using a single-photon avalanche diode (SPAD) array detector. We report biexciton binding energies and assign their charged states, which undergo fast (μs) switching dynamics. Most notably, we identify a spectral feature blue-shifted from the exciton by 7.4 ± 1.9 meV as the bound triexciton and establish the order of its cascade emission. These results highlight the power of low-temperature, multidimensional photon-correlation spectroscopy for resolving complex many-body dynamics.