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0 of 4 missions completed. Current mission: Stimulated Emission. Observe photons triggering emission of identical photons.

Laser Optics Lab

Laser Optics Simulator — Optical Cavity & Gain Medium

This laser optics simulator models a Fabry-Pérot optical cavity with two mirrors (M1 at 100% and M2 at 99% reflectivity) and an active gain medium. Animated photons bounce inside the cavity and are amplified via stimulated emission when the pump rate exceeds 50%, at which point an output beam exits to the right. An energy-level diagram shows excited and ground-state populations with a pump arrow, while a Gaussian gain profile curve at the bottom displays cavity longitudinal modes with red marker lines.

What you can do in this simulation

  • Adjust laser wavelength (400–1100 nm) and gain bandwidth
  • Set pump rate (0–100%) to control lasing threshold and output
  • Vary cavity length (5–100 cm) to change longitudinal mode spacing
  • Select presets: HeNe (632.8 nm), Ar+ (488 nm), Nd:YAG (1064 nm), Ti:Sapphire
  • Watch energy-level population and photon count change in real time

Concepts covered

stimulated emission · optical cavity · laser gain · longitudinal modes · population inversion · Fabry-Pérot resonator

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