Light Amplification by Stimulated Emission of Radiation
Ruby Laser, by T. H. Maiman, 1960
National Ignition Facility, Lawrence Livermore Lab 1.8MJ, 192 Lasers 106J fired every second 106W = 10,000 100W lightbulbs Enough to supply 3000 households
Nova Target Chamber (LBNL) - Laser Fusion
Compact Disc (CD) Reader 1
hn absorption emission Stimulated emission E
Population inversion Mirror Mirror
Spontaneous emission Mirror Mirror
Stimulated emission Mirror Mirror
Feed-back by the cavity Mirror Mirror
Stimulated emission Mirror Mirror
Feed-back by the cavity Mirror Mirror
After several round trips… Mirror Mirror Laser beam Photons with: - same energy : Monochromatic - same direction of propagation : Spatial coherence - all in synchrony: Temporal coherence
strong absorption & emission Dye molecules: strong absorption & emission
To make a dye lase Partial (4%) reflector Pump: UV laser Cylinder Lens
Off to the Lab!