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Efrat Lifshitz
Efrat Lifshitz () is an Israeli chemist at the Schulich Faculty of Chemistry and the Solid-State Institute, Technion – Israel Institute of Technology (Technion-IIT). Lifshitz's research is known for pioneering advances in developing and studying low-dimensional semiconductors by exploring the relationship between their optical properties and magnetism. Biography Lifshitz was born in 1956 in Haifa, Israel. She obtained her B.Sc. in Chemistry in 1979 from the Hebrew University of Jerusalem. She received her M.Sc. (1981) and Ph.D. (1984) in Physical Chemistry from the University of Michigan, U.S.A, working under the supervision of Prof. A. Francis. After receiving her Ph.D., Efrat spent one year (1984-85) as a postdoctoral fellow at the Weizmann Institute of Science, Israel. Lifshitz was a research associate at the University of Michigan from 1986 to 1990, immediately after which she joined the Schulich Faculty of Chemistry at the Technion-IIT as an assistant professor. Lifshi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haifa
Haifa ( ; , ; ) is the List of cities in Israel, third-largest city in Israel—after Jerusalem and Tel Aviv—with a population of in . The city of Haifa forms part of the Haifa metropolitan area, the third-most populous metropolitan area in Israel. It is home to the Baháʼí Faith's Baháʼí World Centre, and is a UNESCO World Heritage Site and a destination for Baháʼí pilgrimage. Built on the slopes of Mount Carmel, the settlement has a history spanning more than 3,000 years. The earliest known settlement in the vicinity was Tell Abu Hawam, a small port city established in the Late Bronze Age (14th century BCE).Encyclopaedia Judaica, Encyclopedia Judaica, ''Haifa'', Keter Publishing, Jerusalem, 1972, vol. 7, pp. 1134–1139 In the 3rd century CE, Haifa was known as a Tool and die maker, dye-making center. Over the millennia, the Haifa area has changed hands: being conquered and ruled by the Canaanites, History of ancient Israel and Judah, Israelites, Phoenicians, Assy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colloidal
A colloid is a mixture in which one substance consisting of microscopically dispersed insoluble particles is suspended throughout another substance. Some definitions specify that the particles must be dispersed in a liquid, while others extend the definition to include substances like aerosols and gels. The term colloidal suspension refers unambiguously to the overall mixture (although a narrower sense of the word '' suspension'' is distinguished from colloids by larger particle size). A colloid has a dispersed phase (the suspended particles) and a continuous phase (the medium of suspension). The dispersed phase particles have a diameter of approximately 1 nanometre to 1 micrometre. Some colloids are translucent because of the Tyndall effect, which is the scattering of light by particles in the colloid. Other colloids may be opaque or have a slight color. Colloidal suspensions are the subject of interface and colloid science. This field of study began in 1845 by Frances ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rashba Effect
The Rashba effect, also called Bychkov–Rashba effect, is a momentum-dependent splitting of spin bands in bulk crystalsMore specifically, uniaxial noncentrosymmetric crystals. and low-dimensional condensed matter systems (such as heterostructures and surface states) similar to the splitting of particles and anti-particles in the Dirac Hamiltonian. The splitting is a combined effect of spin–orbit interaction and asymmetry of the crystal potential, in particular in the direction perpendicular to the two-dimensional plane (as applied to surfaces and heterostructures). This effect is named in honour of Emmanuel Rashba, who discovered it with Valentin I. Sheka in 1959 for three-dimensional systems and afterward with Yurii A. Bychkov in 1984 for two-dimensional systems.Yu. A. Bychkov and E. I. Rashba, Properties of a 2D electron gas with a lifted spectrum degeneracy, Sov. Phys. - JETP Lett. 39, 78-81 (1984) Remarkably, this effect can drive a wide variety of novel physical phenomena ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photoluminescence
Photoluminescence (abbreviated as PL) is light emission from any form of matter after the absorption of photons (electromagnetic radiation). It is one of many forms of luminescence (light emission) and is initiated by photoexcitation (i.e. photons that excite electrons to a higher energy level in an atom), hence the prefix ''photo-''. Following excitation, various relaxation processes typically occur in which other photons are re-radiated. Time periods between absorption and emission may vary: ranging from short femtosecond-regime for emission involving free-carrier plasma in inorganic semiconductorsHayes, G.R.; Deveaud, B. (2002). "Is Luminescence from Quantum Wells Due to Excitons?". ''Physica Status Solidi A'' 190 (3): 637–640doi:10.1002/1521-396X(200204)190:33.0.CO;2-7/ref> up to milliseconds for phosphoresence processes in molecular systems; and under special circumstances delay of emission may even span to minutes or hours. Observation of photoluminescence at a certain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circularly Polarized
In electrodynamics, circular polarization of an electromagnetic wave is a polarization state in which, at each point, the electromagnetic field of the wave has a constant magnitude and is rotating at a constant rate in a plane perpendicular to the direction of the wave. In electrodynamics, the strength and direction of an electric field is defined by its electric field vector. In the case of a circularly polarized wave, the tip of the electric field vector, at a given point in space, relates to the phase of the light as it travels through time and space. At any instant of time, the electric field vector of the wave indicates a point on a helix oriented along the direction of propagation. A circularly polarized wave can rotate in one of two possible senses: ''right-handed circular polarization (RHCP)'' in which the electric field vector rotates in a right-hand sense with respect to the direction of propagation, and ''left-handed circular polarization (LHCP)'' in which the vector r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Confocal Microscopy
Confocal microscopy, most frequently confocal laser scanning microscopy (CLSM) or laser scanning confocal microscopy (LSCM), is an optical imaging technique for increasing optical resolution and contrast (vision), contrast of a micrograph by means of using a Spatial filter, spatial pinhole to block out-of-focus light in image formation. Capturing multiple two-dimensional images at different depths in a sample enables the reconstruction of three-dimensional structures (a process known as optical sectioning) within an object. This technique is used extensively in the scientific and industrial communities and typical applications are in life sciences, semiconductor inspection and materials science. Light travels through the sample under a conventional microscope as far into the specimen as it can penetrate, while a confocal microscope only focuses a smaller beam of light at one narrow depth level at a time. The CLSM achieves a controlled and highly limited depth of field. Basic c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optically Detected Magnetic Resonance
In physics, optically detected magnetic resonance (ODMR) is a technique for detecting quantum objects that are both paramagnetic and optically active. In the case of photoluminescent point defects ( color centers) in crystals, the “ODMR signal” usually means a decrease in the defect’s fluorescence intensity under continuous illumination due to a simultaneously applied AC magnetic field. The AC magnetic field induces Rabi oscillations of the fluorescing electrons, which as a result rapidly transition between an optically active state and an optically inactive state, decreasing the overall fluorescence signal. By varying the frequency of the AC magnetic field, (often referred to as the RF field due to the typical frequency used), the resonance frequency of a particular transition can be measured since the resonant RF field induces a marked decrease in fluorescence intensity. There may be many such transitions, and their characteristics as observed with ODMR (principally frequen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perovskite Nanocrystal
Perovskite nanocrystals are a class of semiconductor nanocrystals, which exhibit unique characteristics that separate them from traditional quantum dots. Perovskite (structure), Perovskite nanocrystals have an ABX3 composition where A = Caesium, cesium, Methylammonium halide, methylammonium (MA), or formamidinium (FA); B = lead or tin; and X = chloride, bromide, or iodide. Their unique qualities largely involve their unusual Electronic band structure, band-structure which renders these materials effectively Dangling bond, defect tolerant or able to emit brightly without surface passivation. This is in contrast to other quantum dots such as Cadmium selenide, CdSe which must be passivated with an Epitaxy, epitaxially matched shell to be bright emitters. In addition to this, lead-halide perovskite nanocrystals remain bright emitters when the size of the nanocrystal imposes only weak quantum confinement. This enables the production of nanocrystals that exhibit narrow emission linewidt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
