VERTICAL CAVITY SURFACE EMITTING LASER (SEMICONDUCTOR LASERS) ECE 631 INSTRUCTOR: Prof. Celal Zaim Çil Reşat ŞEKER 2013
HOW IT WORKS: Homojunction Structures Semiconductor lasers are diodes which are electrically pumped. Recombination of electrons and holes created by the applied current introduces optical gain. Reflection from the ends of the crystal form an optical resonator, although the resonator can be external to the semiconductor in some designs.
-Electron and holes energies are quantized in the confinement direction (Z or thickness in this case) and continuous in other two directions Heterojunction Lasers (Quantum cascade Lasers)
-QCLs are typically based upon a three level system.
Quantun confined materials Properties of bulk inorganic semi conductors
QUANTUM CONFINED STRUCTURES AS LASING MEDIA
APPLICATIONS -Military Applications (Target maker-Range Finder) -Communication Systems (Fiberoptic transmitters) -Medical Surgery -Optic Media (Cd-DVD-BlueRay Reader Writer) -Measurement Systems (3d Scanners - Surveying equipment, total stations- laser meters) -Entertainment (Laser shows) -Printer technology
Properties - Consists of quantum structures -Small size -Non-maintenance -Long life time -Simple usage -Too many usage area -Stability -Tunable wavelenght