Related Research Articles
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The word "laser" is an acronym for "light amplification by stimulated emission of radiation". The first laser was built in 1960 by Theodore H. Maiman at Hughes Research Laboratories, based on theoretical work by Charles Hard Townes and Arthur Leonard Schawlow.
In quantum mechanics, the particle in a box model describes a particle free to move in a small space surrounded by impenetrable barriers. The model is mainly used as a hypothetical example to illustrate the differences between classical and quantum systems. In classical systems, for example, a particle trapped inside a large box can move at any speed within the box and it is no more likely to be found at one position than another. However, when the well becomes very narrow, quantum effects become important. The particle may only occupy certain positive energy levels. Likewise, it can never have zero energy, meaning that the particle can never "sit still". Additionally, it is more likely to be found at certain positions than at others, depending on its energy level. The particle may never be detected at certain positions, known as spatial nodes.
Atomic, molecular, and optical physics (AMO) is the study of matter-matter and light-matter interactions; at the scale of one or a few atoms and energy scales around several electron volts. The three areas are closely interrelated. AMO theory includes classical, semi-classical and quantum treatments. Typically, the theory and applications of emission, absorption, scattering of electromagnetic radiation (light) from excited atoms and molecules, analysis of spectroscopy, generation of lasers and masers, and the optical properties of matter in general, fall into these categories.
A laser diode is a semiconductor device similar to a light-emitting diode in which a diode pumped directly with electrical current can create lasing conditions at the diode's junction.
Laser cooling and laser trapping include a number of techniques in which atomic and molecular samples are cooled down to near absolute zero. Laser cooling techniques rely on the fact that when an object absorbs and re-emits a photon its momentum changes. For an ensemble of particles, their thermodynamic temperature is proportional to the variance in their velocity. That is, more homogeneous velocities among particles corresponds to a lower temperature. Laser cooling techniques combine atomic spectroscopy with the aforementioned mechanical effect of light to compress the velocity distribution of an ensemble of particles, thereby cooling the particles. The 1997 Nobel Prize in Physics was awarded to Claude Cohen-Tannoudji, Steven Chu, and William Daniel Phillips "for development of methods to cool and trap atoms with laser light".
In physics, two wave sources are coherent if their frequency and waveform are identical. Coherence is an ideal property of waves that enables stationary interference. It contains several distinct concepts, which are limiting cases that never quite occur in reality but allow an understanding of the physics of waves, and has become a very important concept in quantum physics. More generally, coherence describes all properties of the correlation between physical quantities of a single wave, or between several waves or wave packets.
A quantum well is a potential well with only discrete energy values.
Quantum optics is a branch of atomic, molecular, and optical physics dealing with how individual quanta of light, known as photons, interact with atoms and molecules. It includes the study of the particle-like properties of photons. Photons have been used to test many of the counter-intuitive predictions of quantum mechanics, such as entanglement and teleportation, and are a useful resource for quantum information processing.
A quantum dot laser is a semiconductor laser that uses quantum dots as the active laser medium in its light emitting region. Due to the tight confinement of charge carriers in quantum dots, they exhibit an electronic structure similar to atoms. Lasers fabricated from such an active media exhibit device performance that is closer to gas lasers, and avoid some of the negative aspects of device performance associated with traditional semiconductor lasers based on bulk or quantum well active media. Improvements in modulation bandwidth, lasing threshold, relative intensity noise, linewidth enhancement factor and temperature insensitivity have all been observed. The quantum dot active region may also be engineered to operate at different wavelengths by varying dot size and composition. This allows quantum dot lasers to be fabricated to operate at wavelengths previously not possible using semiconductor laser technology.
An optical lattice is formed by the interference of counter-propagating laser beams, creating a spatially periodic polarization pattern. The resulting periodic potential may trap neutral atoms via the Stark shift. Atoms are cooled and congregate at the potential extrema. The resulting arrangement of trapped atoms resembles a crystal lattice and can be used for quantum simulation.
Federico Capasso, a prominent applied physicist, was one of the inventors of the quantum cascade laser during his work at Bell Laboratories. He is currently on the faculty of Harvard University. He has co-authored over 450 papers, edited four volumes, and holds over 60 US patents.
Isamu Akasaki was a Japanese engineer and physicist, specializing in the field of semiconductor technology and Nobel Prize laureate, best known for inventing the bright gallium nitride (GaN) p-n junction blue LED in 1989 and subsequently the high-brightness GaN blue LED as well.
The Max-Planck-Institute for Quantum Optics is a part of the Max Planck Society which operates 87 research facilities in Germany.
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 are able to emit light efficiently. 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. This means that much shorter wavelengths can be obtained from quantum well lasers than from conventional laser diodes using a particular semiconductor material. The efficiency of a quantum well laser is also greater than a conventional laser diode due to the stepwise form of its density of states function.
Alfred ("Alf") Rodney Adams, FRS 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.
Crosslight Software Inc. is an international company headquartered in greater Vancouver, British Columbia, Canada. Officially spun off from the National Research Council of Canada (NRC) in 1995, it provides Technology Computer Aided Design (TCAD) tools for semiconductor device and process simulations.
Eoin P. O’Reilly is an Irish physicist who, as of 2014, was chief scientific officer at the Tyndall Institute, and a professor of physics at University College Cork. In 2014 he was awarded the Rank Prize in Optoelectronics for his pioneering work on strained-layer laser structures.
Shun Lien Chuang was an American engineer, scientist, Fellow of the IEEE, OSA, APS and JSPS, and Professor at the University of Illinois at Urbana-Champaign.
James J. Coleman is an electrical engineer who worked at Bell Labs, Rockwell International, and the University of Illinois, Urbana. He is best known for his work on semiconductor lasers, materials and devices including strained-layer indium gallium arsenide lasers and selective area epitaxy. Coleman is a Fellow of the IEEE and a member of the US National Academy of Engineering.
References
- 1 2 "A catalyst to our digital world: strained quantum well lasers—Full Case Study". SET squared. Universities of Bath, Bristol, Exetor, Southampton & Surrey. Retrieved 2 April 2015.
 | This technology-related article is a stub. You can help Wikipedia by expanding it. |