Quantum Cascade Laser
Quantum cascade lasers (QCLs) are semiconductor lasers that emit in the mid- to far-infrared portion of the electromagnetic spectrum and were first demonstrated by Jerome Faist, Federico Capasso, Deborah Sivco, Carlo Sirtori, Albert Hutchinson, and Alfred Cho at Bell Laboratories in 1994.
Unlike typical interband semiconductor lasers that emit electromagnetic radiation through the recombination of electron–hole pairs across the material band gap, QCLs are unipolar and laser emission is achieved through the use of intersubband transitions in a repeated stack of semiconductor multiple quantum well heterostructures, an idea first proposed in the paper "Possibility of amplification of electromagnetic waves in a semiconductor with a superlattice" by R.F. Kazarinov and R.A. Suris in 1971.
... a prominent applied physicist, was one of the inventors of the quantum cascade laser during his work at Bell Laboratories ... held several management positions at Bell Labs including Head of the Quantum Phenomena and Device Research Department and the Semiconductor Physics Research ... He applied it to novel low noise quantum well avalanche photodiodes, heterojunction transistors, memory devices and lasers ...
1994 Quantum cascade laser A quantum cascade laser is a sliver of semiconductor material about the size of a tick ... within layers of gallium and aluminum compounds, called quantum wells are nanometers thick, much smaller than the thickness of a hair ... The quantum cascade laser was co-invented by Alfred Y ...
... Distributed feedback (DFB) quantum cascade lasers were first commercialized in 2004, and broadly-tunable external cavity quantum cascade lasers first commercialized ... When used in multiple-laser systems, intrapulse QCL spectroscopy offers broadband spectral coverage that can potentially be used to identify and quantify ...
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