A strained quantum well laser is a type of

quantum-well laser A quantum well laser is a laser diode in which the active region of the device is so narrow that quantum confinement occurs. Laser diodes are formed in compound semiconductor materials that (quite unlike silicon) are able to emit light efficientl ...

, which was invented by Professor

Alf Adams Alfred ("Alf") Rodney Adams, FRS (born 1939) is a British physicist who invented the strained-layer quantum-well laser. Most modern homes will have several of these devices in their homes in all types of electronic equipment. He served as a D ...

at the

University of Surrey The University of Surrey is a public research university in Guildford, Surrey, England. The university received its royal charter in 1966, along with a number of other institutions following recommendations in the Robbins Report. The institut ...

in 1986. The laser is distinctive for producing a more concentrated beam than other

quantum well A quantum well is a potential well with only discrete energy values. The classic model used to demonstrate a quantum well is to confine particles, which were initially free to move in three dimensions, to two dimensions, by forcing them to occupy ...

lasers, making it considerably more efficient. The lasers are notable for usage in CD, DVD, and Blu-Ray drives as well as applications in supermarket

barcode reader A barcode reader is an optical scanner that can read printed barcodes, decode the data contained in the barcode to a computer. Like a flatbed scanner, it consists of a light source, a lens and a light sensor for translating optical impulses into e ...

s and

telephone A telephone is a telecommunications device that permits two or more users to conduct a conversation when they are too far apart to be easily heard directly. A telephone converts sound, typically and most efficiently the human voice, into e ...

optical transmission.

References

Semiconductor lasers Photonics Quantum optics British inventions {{tech-stub