Parkinson's group uses ultrafast optical spectroscopy to study carrier dynamics in photonic materials with quantum device applications. Research directions: (1) Time-resolved photoluminescence — TRPL with single-photon counting to map exciton lifetimes, diffusion, and defect trapping in GaN, perovskite, and 2D semiconductor quantum wells; (2) Optical single-particle spectroscopy — isolating single nanowires or nanocrystals for defect-free measurements of intrinsic optical properties; (3) Photon-number statistics — Hanbury Brown–Twiss measurements of single-photon purity from quantum dots and localized excitons; (4) Semiconductor quantum sensing interfaces — studying how carrier dynamics affect the fidelity of semiconductor-based quantum sensors and emitters.