Refractive indexIn optics, the refractive index (also called refraction index or index of refraction), often denoted n, is the ratio of the speed of light in vacuum (c) to the speed of light in a given optical medium (v), n=c/v. The refractive index determines how much the path of light is bent, or refracted, when entering a material, as described by Snell's law of refraction, n1 sin θ1 = n2 sin θ2, where θ1 and θ2 are the angle of incidence and angle of refraction, respectively, of a ray crossing the interface between two media with refractive indices n1 and n2.
Group velocityThe group velocity of a wave is the velocity with which the overall envelope shape of the wave's amplitudes—known as the modulation or envelope of the wave—propagates through space. For example, if a stone is thrown into the middle of a very still pond, a circular pattern of waves with a quiescent center appears in the water, also known as a capillary wave.
Speed of lightThe speed of light is the speed of electromagnetic waves. Light travels at slower speed inside materials like glass or water; its highest speed is in a vacuum. The speed of light in vacuum is a universal physical constant denoted c (in ISO and IEC standards c0), exactly equal to 299792458 m⋅s−1. It is exact because, by international agreement, a metre is defined as the length of the path travelled by light in vacuum during a time interval of 1⁄299792458 second.
Electromagnetically induced transparencyElectromagnetically induced transparency (EIT) is a coherentopticalnonlinearity which renders a medium transparent within a narrow spectral range around an absorption line. Extreme dispersion is also created within this transparency "window" which leads to "slow light", described below. It is in essence a quantum interference effect that permits the propagation of light through an otherwise opaque atomic medium.
Phase velocityThe phase velocity of a wave is the speed of any wavefront, a surface of constant phase. This is the velocity at which the phase of any constant-frequency component of the wave travels. For such a spectral component, any given phase of the wave (for example, the crest) will appear to travel at the phase velocity. The phase velocity of light waves is not a physically meaningful quantity and is not related to information transfer.
Lene HauLene Vestergaard Hau (Danish:; born November 13, 1959) is a Danish physicist and educator. She is the Mallinckrodt Professor of Physics and of Applied Physics at Harvard University. In 1999, she led a Harvard University team that, by use of a Bose–Einstein condensate, succeeded in slowing a beam of light to about 17 metres per second, and, in 2001, was able to stop a beam completely.OpticsOptics is the branch of physics that studies the behaviour, manipulation, and detection of electromagnetic radiation, including its interactions with matter and instruments that use or detect it. Optics usually describes the behaviour of visible, ultraviolet, and infrared light. The study of optics extends to other forms of electromagnetic radiation, including radio waves, microwaves, and X-rays.
SemiconductorA semiconductor is a material with electrical conductivity between that of a conductor and an insulator. Its conductivity can be modified by adding impurities ("doping") to its crystal structure. When two regions with different doping levels are present in the same crystal, they form a semiconductor junction.
Stephen E. HarrisStephen Ernest Harris (born November 29, 1936) is an American physicist known for his contributions to electromagnetically induced transparency (EIT), modulation of single photons, and x-ray emission.
Integrated circuitElectronic circuit formed on a small, flat piece of semiconductor materialA microscope image of an integrated circuit die used to control LCDs. The pinouts are the dark circles surrounding the integrated circuit.An integrated circuit (IC), also known as a microchip or simply chip, is a compact assembly of electronic circuits formed from various electronic components, such as transistors, resistors, and capacitors, and their interconnections.
Harvard UniversityPrivate university in Cambridge, Massachusetts, USHarvard University is a privateIvy Leagueresearch university in Cambridge, Massachusetts, United States. Founded in 1636, and named Harvard College in 1639 in honor of its first benefactor, Puritan clergyman John Harvard, it is the oldest institution of higher learning in the United States. Its influence, wealth, and rankings have made it one of the most prestigious universities in the world.
University of California, BerkeleyPublic university in Berkeley, CaliforniaThe University of California, Berkeley (UC Berkeley, Berkeley, Cal, or California) is a publicland-grantresearch university in Berkeley, California, United States. Founded in 1868 and named after the Anglo-Irish philosopher and clergyman George Berkeley, it is the state's first land-grant university and the founding campus of the University of California system. Berkeley has an enrollment of more than 45,000 students.
IBMInternational Business Machines Corporation (IBM) is an American multinational technology company headquartered in Armonk, New York, and present in over 175 countries. It is a publicly traded company and one of the 30 companies in the Dow Jones Industrial Average.*As an Amazon Associate I earn from qualifying purchases.