The wavelength of the light emitted by a quantum-well laser is determined by the width of the active region rather than just the bandgap of the materials from which it is constructed.
In addition to Henry's contributions, the quantum well (which is a type of double-heterostructure laser) was actually first proposed in 1963 by Herbert Kroemer in Proceedings of the IEEE[2] and simultaneously (in 1963) in the U.S.S.R by Zh.
[1] The first electrically pumped "injection" quantum-well laser was observed[9] by P. Daniel Dapkus and Russell D. Dupuis of Rockwell International, in collaboration with the University of Illinois at Urbana Champaign (Holonyak) group in 1977.
Dapkus and Dupuis had, by then, pioneered the metalorganic vapour phase epitaxy MOVPE (also known as OMCVD, OMVPE, and MOCVD) technique for fabricating semiconductor layers.
The MOVPE technique, at the time, provided superior radiative efficiency as compared to the molecular beam epitaxy (MBE) used by Bell Labs.
Later, however, Won T. Tsang at Bell Laboratories succeeded in using MBE techniques in the late 1970s and early 1980s to demonstrate dramatic improvements in performance of quantum-well lasers.
Tsang showed that, when quantum wells are optimized, they have exceedingly low threshold current and very high efficiency in converting current-in to light-out, making them ideal for widespread use.
[10][full citation needed] Extensive work has been performed on quantum-well lasers based on gallium arsenide and indium phosphide wafers.
by Peter S. Zory, Jr.[1] Quantum-well lasers are important because they are the basic active element (laser-light source) of the Internet's fiber-optic communication backbone.
[citation needed] Early work on these lasers focused on GaAs gallium arsenide based wells bounded by Al–GaAs walls, but wavelengths transmitted by optical fibers are best achieved with indium phosphide walls with indium gallium arsenide phosphide based wells.
[citation needed] Commercial success was achieved by Lucent (a spin-off from Bell Laboratories) in the early 1990s with quality control of quantum-well laser production by MOVPE Metalorganic vapour phase epitaxy, as done using high-resolution X rays by Joanna (Joka) Maria Vandenberg.
[citation needed] Multiple Quantum Well III-nitride diodes feature an overlapping region between the wavelengths they emit and detect.