Quantum-Dot Avalanche Photodiode: Impact-Ionization Gain

This simulator visualizes avalanche multiplication in a quantum-dot avalanche photodiode's high-field region: a single photon absorbed at the quantum-dot layer injects one electron, which drifts through the multiplication zone and can trigger impact-ionization events that branch into a full electron-hole cascade. Reverse bias and the electron/hole ionization ratio k = β/α are both adjustable, driving the exact McIntyre local-field gain formula M = (1−k)/[exp(−(1−k)αL) − k] and its excess noise factor F(M) = kM + (1−k)(2 − 1/M), while a live Monte-Carlo particle cascade lets you watch the same statistics play out carrier by carrier and see the measured gain fluctuate around the analytic prediction.