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Attophysics
Attosecond physics, also known as attophysics, or more generally attosecond science, is a branch of physics that deals with light-matter interaction phenomena wherein attosecond (10−18 s) photon pulses are used to unravel dynamical processes in matter with unprecedented time resolution. Attosecond science mainly employs pump–probe spectroscopic methods to investigate the physical process of interest. Due to the complexity of this field of study, it generally requires a synergistic interplay between state-of-the-art experimental setup and advanced theoretical tools to interpret the data collected from attosecond experiments. The main interests of attosecond physics are: # Atomic physics: investigation of electron correlation effects, photo-emission delay and ionization tunneling. # Molecular physics and molecular chemistry: role of electronic motion in molecular excited states (e.g. charge-transfer processes), light-induced photo-fragmentation, and light-induced electron t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carrier Envelope Offset Control
In optics, a frequency comb is a laser source whose spectrum consists of a series of discrete, equally spaced frequency lines. Frequency combs can be generated by a number of mechanisms, including periodic modulation (in amplitude and/or phase) of a continuous-wave laser, four-wave mixing in nonlinear media, or stabilization of the pulse train generated by a mode-locked laser. Much work has been devoted to this last mechanism, which was developed around the turn of the 21st century and ultimately led to one half of the Nobel Prize in Physics being shared by John L. Hall and Theodor W. Hänsch in 2005. The frequency domain representation of a perfect frequency comb is a series of delta functions spaced according to : f_n = f_0 + n\,f_r, where n is an integer, f_r is the comb tooth spacing (equal to the mode-locked laser's repetition rate or, alternatively, the modulation frequency), and f_0 is the carrier offset frequency, which is less than f_r. Combs spanning an octave in freq ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Femtochemistry
Femtochemistry is the area of physical chemistry that studies chemical reactions on extremely short timescales (approximately 10−15 seconds or one femtosecond, hence the name) in order to study the very act of atoms within molecules (reactants) rearranging themselves to form new molecules (products). In a 1988 issue of the journal ''Science'', Ahmed Hassan Zewail published an article using this term for the first time, stating "Real-time femtochemistry, that is, chemistry on the femtosecond timescale...". Later in 1999, Zewail received the Nobel Prize in Chemistry for his pioneering work in this field showing that it is possible to see how atoms in a molecule move during a chemical reaction with flashes of laser light. Application of femtochemistry in biological studies has also helped to elucidate the conformational dynamics of stem-loop RNA structures. Many publications have discussed the possibility of controlling chemical reactions by this method, but this remains cont ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ferenc Krausz
Ferenc Krausz (born 17 May 1962 in Mór, Hungary) is a Hungarian-Austrians, Austrian physicist, whose research team has generated and measured the first attosecond pulse (physics), light pulse and used it for capturing electrons’ motion inside atoms, marking the birth of attophysics. Academic career Krausz studied theoretical physics at Eötvös Loránd University and electrical engineering at the Technical University of Budapest in Hungary. After his habilitation at the Technical University of Vienna, in Austria, he became professor at the same institute. In 2003 he was appointed director at the Max Planck Institute for Quantum Optics in Garching and in 2004 became chair of experimental physics at the Ludwig Maximilians University in Munich. In 2006 he co-founded the Munich-Centre of Advanced Photonics (MAP) and began serving as one of its directors. Research Ferenc Krausz and his research team were the first to create and measure a light pulse lasting less than one femt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anne L'Huillier
Anne L'Huillier (born 1958 in Paris) is a French physicist, and professor of atomic physics at Lund University in Sweden. Life L'Huillier first pursued an education and was awarded a Master of Science in theoretical physics and mathematics, but switched for her PhD to experimental physics at the French nuclear research center of the Commissariat à l'énergie atomique et aux énergies alternatives in Saclay Nuclear Research Centre. Her dissertation was on multiple ionization in laser fields of high intensity. As a post-doctoral student, she was in Gothenburg, Sweden and Los Angeles, California, United States. From 1986, she was permanently employed at the Saclay Nuclear Research Centre. In 1992, she took part in an experiment in Lund, where one of the first titanium-sapphire solid-state laser systems for femtosecond pulses in Europe had been installed. In 1994 she moved to Sweden, where she served at Lund University as a lecturer in 1995 and a professor in 1997. She leads an at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spin (physics)
Spin is a conserved quantity carried by elementary particles, and thus by composite particles (hadrons) and atomic nucleus, atomic nuclei. Spin is one of two types of angular momentum in quantum mechanics, the other being ''orbital angular momentum''. The orbital angular momentum operator is the quantum-mechanical counterpart to the classical angular momentum of orbital revolution and appears when there is periodic structure to its wavefunction as the angle varies. For photons, spin is the quantum-mechanical counterpart of the Polarization (waves), polarization of light; for electrons, the spin has no classical counterpart. The existence of electron spin angular momentum is inferred from experiments, such as the Stern–Gerlach experiment, in which silver atoms were observed to possess two possible discrete angular momenta despite having no orbital angular momentum. The existence of the electron spin can also be inferred theoretically from the spin–statistics theorem and from th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chirped Mirror
A chirped mirror is a dielectric mirror with chirped spaces—spaces of varying depth designed to reflect varying wavelengths of lights—between the dielectric layers (stack). Chirped mirrors are used in applications like lasers to reflect a wider range of light wavelengths than ordinary dielectric mirrors, or to compensate for the dispersion of wavelengths that can be created by some optical elements. Chirped mirrors are also found in structurally colored biological systems, including the shiny golden and silver color of certain beetles' elytra, e.g. those of the Ruteline genus ''Chrysina''. In these cases, the chirped mirror generates complex color (such as gold or silver) when illuminated by white light by simultaneously reflecting a broad range of monochromatic colors. Simple explanation An ordinary dielectric mirror is made to reflect a single frequency of light. The dielectric mirror is made of transparent materials that are uniformly layered at a depth of 1/4 the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Self-phase Modulation
Self-phase modulation (SPM) is a nonlinear optical effect of light–matter interaction. An ultrashort pulse of light, when travelling in a medium, will induce a varying refractive index of the medium due to the optical Kerr effect. This variation in refractive index will produce a phase shift in the pulse, leading to a change of the pulse's frequency spectrum. Self-phase modulation is an important effect in optical systems that use short, intense pulses of light, such as lasers and optical fiber communications systems. Self-phase modulation has also been reported for nonlinear sound waves propagating in biological thin films, where the phase modulation results from varying elastic properties of the lipid films. Theory with Kerr nonlinearity The evolution along distance ''z'' of the equivalent lowpass electric field ''A(z)'' obeys the nonlinear Schrödinger equation which, in absence of dispersion, is: :\frac = -j\gamma \left, A(z)\^2 A(z) with ''j'' the imaginary unit and ''Π... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chirped Pulse Amplification
Chirped pulse amplification (CPA) is a technique for amplifying an ultrashort laser pulse up to the petawatt level, with the laser pulse being stretched out temporally and spectrally, then amplified, and then compressed again. The stretching and compression uses devices that ensure that the different color components of the pulse travel different distances. CPA for lasers was introduced by Donna Strickland and Gérard Mourou at the University of Rochester in the mid-1980s, work for which they received the Nobel Prize in Physics in 2018. CPA is the current state-of-the-art technique used by most of the highest-power lasers in the world. Background Before the introduction of CPA in the mid-1980s, the peak power of laser pulses was limited because a laser pulse at intensities of gigawatts per square centimeter causes serious damage to the gain medium through nonlinear processes such as self-focusing. For example, some of the most powerful compressed CPA laser beams, even in an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wolf Prize
The Wolf Prize is an international award granted in Israel, that has been presented most years since 1978 to living scientists and artists for ''"achievements in the interest of mankind and friendly relations among people ... irrespective of nationality, race, colour, religion, sex or political views."'' History The prize is awarded in Israel by the Wolf Foundation, founded by Ricardo Wolf, a German-born inventor and former Cuban ambassador to Israel. It is awarded in six fields: Agriculture, Chemistry, Mathematics, Medicine, Physics, and an Arts prize that rotates between architecture, music, painting, and sculpture. Each prize consists of a diploma and US$100,000. The awards ceremony typically takes place at a session in the Knesset. The prize is described by the Foundation as being "awarded annually", but is not in fact awarded every year: between 2000 and 2010, only six prizes were awarded in most fields, and only four in Physics. The Wolf Prizes in Physics and Chemistry ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paul Corkum
Paul Bruce Corkum (born October 30, 1943) is a Canadian physicist specializing in attosecond physics and laser science., as published in '' Physics in Canada'', 65(2) 58. He holds a joint University of Ottawa– NRC chair in Attosecond Photonics. He is one of the students of strong field atomic physics, ''i.e.'' atoms and plasmas in super-intense laser fields. Biography and research Corkum was born in Saint John, New Brunswick. He obtained his BSc (1965) from Acadia University, Nova Scotia, and his MSc (1967) and PhD (1972) in theoretical physics from Lehigh University, Pennsylvania. He won several awards for his work on laser science. Corkum is both a theorist and an experimentalist. In the 1980s he developed a model of the ionization of atoms (''i.e.'' plasma production) and on this basis proposed a new approach to making X-ray lasers (Optical field Ionization, OFI). OFI lasers are today one of the most important developments in X-ray laser research. In the early 1990s in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reports On Progress In Physics
''Reports on Progress in Physics'' is a monthly peer review, peer-reviewed scientific journal published by IOP Publishing. The editor-in-chief as of 2022 is Subir Sachdev (Harvard University). Scope The focus of this journal is invited review articles covering all branches of physics. Each review will typically survey and critique a particular topic, or developments in a field. Introductions of articles are intended for a broad readership, beyond the specialist or expert. In addition to the traditional review article two other formats are available: ''Reports on Progress'' (about 20 pages) and ''Key Issues Reviews'' (about 10 pages).Scope IOP. Retrieved on Sep. 5, 2016 Abstracting and indexing ''Reports on Progress in Physics'' is abstracted and indexed in the following databases:[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Matter
In classical physics and general chemistry, matter is any substance that has mass and takes up space by having volume. All everyday objects that can be touched are ultimately composed of atoms, which are made up of interacting subatomic particles, and in everyday as well as scientific usage, "matter" generally includes atoms and anything made up of them, and any particles (or combination of particles) that act as if they have both rest mass and volume. However it does not include massless particles such as photons, or other energy phenomena or waves such as light or heat. Matter exists in various states (also known as phases). These include classical everyday phases such as solid, liquid, and gas – for example water exists as ice, liquid water, and gaseous steam – but other states are possible, including plasma, Bose–Einstein condensates, fermionic condensates, and quark–gluon plasma. Usually atoms can be imagined as a nucleus of protons and neutrons, and a surro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
