Assess students’ ability to design a closed-loop control system for a quantum‑dot single‑photon source to maximize photon indistinguishability and brightness. Require specification of device architecture (QD embedding, cavity/waveguide coupling, cryogenics, electrical/optical actuators and detectors), selection and justification of feedback algorithms (PID, Kalman filtering, adaptive/Bayesian estimation), identification and mitigation of noise sources (temperature drift, spectral diffusion, charge/phonon noise, electronic jitter), and definition of performance metrics and validation methods (HOM visibility, g(2)(0), brightness/efficiency, linewidth, latency, stability). Include trade‑off analysis and implementation considerations for real-time control and sensing.