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Surface science is the study of physical and chemical phenomena that occur at the interface of two phases, including solid–liquid interfaces, solid–gas interfaces, solid–vacuum interfaces, and liquid–surface chemistry and surface physics. Some related practical applications are classed as surface engineering. The science encompasses concepts such as heterogeneous catalysis, semiconductor device fabrication, fuel cells, self-assembled monolayers, and adhesives. Surface science is closely related to interface and colloid science. Interfacial chemistry and physics are common subjects for both. The methods are different. In addition, interface and colloid science studies macroscopic phenomena that occur in heterogeneous systems due to peculiarities of interfaces.
In physics, a plasmon is a quantum of plasma oscillation. Just as light consists of photons, the plasma oscillation consists of plasmons. The plasmon can be considered as a quasiparticle since it arises from the quantization of plasma oscillations, just like phonons are quantizations of mechanical vibrations. Thus, plasmons are collective oscillations of the free electron gas density. For example, at optical frequencies, plasmons can couple with a photon to create another quasiparticle called a plasmon polariton.
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LeRoy W. Apker was an American experimental physicist. Along with his colleagues E. A. Taft and Jean Dickey, he studied the photoelectric emission of electrons from semiconductors and discovered the phenomenon of exciton-induced photoemission in potassium iodide. In 1955, he received the Oliver E. Buckley Condensed Matter Prize of the American Physical Society for his work.
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Terahertz spectroscopy detects and controls properties of matter with electromagnetic fields that are in the frequency range between a few hundred gigahertz and several terahertz. In many-body systems, several of the relevant states have an energy difference that matches with the energy of a THz photon. Therefore, THz spectroscopy provides a particularly powerful method in resolving and controlling individual transitions between different many-body states. By doing this, one gains new insights about many-body quantum kinetics and how that can be utilized in developing new technologies that are optimized up to the elementary quantum level.
A photoinjector is a type of source for intense electron beams which relies on the photoelectric effect. A laser pulse incident onto the cathode of a photoinjector drives electrons out of it, and into the accelerating field of the electron gun. In comparison with the widespread thermionic electron gun, photoinjectors produce electron beams of higher brightness, which means more particles packed into smaller volume of phase space. Photoinjectors serve as the main electron source for single-pass synchrotron light sources, such as free-electron lasers and for ultrafast electron diffraction setups. The first RF photoinjector was developed in 1985 at Los Alamos National Laboratory and used as the source for a free-electron-laser experiment. High-brightness electron beams produced by photoinjectors are used directly or indirectly to probe the molecular, atomic and nuclear structure of matter for fundamental research, as well as material characterization.
Ortwin Hess is a German-born theoretical physicist at Trinity College Dublin (Ireland) and Imperial College London (UK), working in condensed matter optics. Bridging condensed matter theory and quantum optics he specialises in quantum nanophotonics, plasmonics, metamaterials and semiconductor laser dynamics. Since the late 1980s he has been an author and coauthor of over 300 peer-reviewed articles, the most popular of which, called "'Trapped rainbow' storage of light in metamaterials", was cited more than 400 times. He pioneered active nanoplasmonics and metamaterials with quantum gain and in 2014 he introduced the "stopped-light lasing" principle as a novel route to cavity-free (nano-) lasing and localisation of amplified surface plasmon polaritons, giving him an h-index of 33.
Time-resolved two-photon photoelectron (2PPE) spectroscopy is a time-resolved spectroscopy technique which is used to study electronic structure and electronic excitations at surfaces. The technique utilizes femtosecond to picosecond laser pulses in order to first photoexcite an electron. After a time delay, the excited electron is photoemitted into a free electron state by a second pulse. The kinetic energy and the emission angle of the photoelectron are measured in an electron energy analyzer. To facilitate investigations on the population and relaxation pathways of the excitation, this measurement is performed at different time delays.
Helen H. Fielding is a Professor of physical chemistry at University College London (UCL). She focuses on ultrafast transient spectroscopy of protein chromophores and molecules. She was the first woman to win the Royal Society of Chemistry (RSC) Harrison-Meldola Memorial Prize (1996) and Marlow Award (2001).
Ultrafast scanning electron microscopy (UFSEM) combines two microscopic modalities, Pump-probe microscopy and Scanning electron microscope, to gather temporal and spatial resolution phenomena. The technique uses ultrashort laser pulses for pump excitation of the material and the sample response will be detected by an Everhart-Thornley detector. Acquiring data depends mainly on formation of images by raster scan mode after pumping with short laser pulse at different delay times. The characterization of the output image will be done through the temporal resolution aspect. Thus, the idea is to exploit the shorter DeBroglie wavelength in respect to the photons which has great impact to increase the resolution about 1 nm. That technique is an up-to-date approach to study the dynamic of charge on material surfaces.
In physics and chemistry, photoemission orbital tomography is a combined experimental / theoretical approach which was initially developed to reveal information about the spatial distribution of individual one-electron surface-state wave functions and later exteded to study molecular orbitals. Experimentally, it uses angle-resolved photoemission spectroscopy (ARPES) to obtain constant binding energy photoemission angular distribution maps. In their pioneering work, Mugarza et al. in 2003 used a phase-retrieval method to obtain the wave function of electron surface states based on ARPES data acquired from stepped gold crystalline surfaces; they obtained the respective wave functions and, upon insertion into the Schrödinger equation, also the binding potential. More recently, photoemission maps, also known as tomograms, have been shown to reveal information about the electron probability distribution in molecular orbitals. Theoretically, one rationalizes these tomograms as hemispherical cuts through the molecular orbital in momentum space. This interpretation relies on the assumption of a plane wave final state, i.e., the idea that the outgoing electron can be treated as a free electron, which can be further exploited to reconstruct real-space images of molecular orbitals on a sub-Ångström length scale in two or three dimensions. Presently, POT has been applied to various organic molecules forming well-oriented monolayers on single crystal surfaces or to two-dimensional materials.
Nano Angle-Resolved Photoemission Spectroscopy (Nano-ARPES), is a variant of the experimental technique ARPES. It has the ability to precisely determine the electronic band structure of materials in momentum space with submicron lateral resolution. Due to its demanding experimental setup, this technique is much less extended than ARPES, widely used in condensed matter physics to experimentally determine the electronic properties of a broad range of crystalline materials. Nano-ARPES can access the electronic structure of well-ordered monocrystalline solids with high energy, momentum, and lateral resolution, even if they are nanometric or heterogeneous mesoscopic samples. Nano-ARPES technique is also based on Einstein's photoelectric effect, being photon-in electron-out spectroscopy, which has converted into an essential tool in studying the electronic structure of nanomaterials, like quantum and low dimensional materials.
References
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- ↑ Minato, Taketoshi; Sainoo, Yasuyuki; Kim, Yousoo; Kato, Hiroyuki S.; Aika, Ken-ichi; Kawai, Maki; Zhao, Jin; Petek, Hrvoje; Huang, Tian; He, Wei; Wang, Bing (2009-03-23). "The electronic structure of oxygen atom vacancy and hydroxyl impurity defects on titanium dioxide (110) surface". The Journal of Chemical Physics. 130 (12): 124502. Bibcode:2009JChPh.130l4502M. doi:10.1063/1.3082408. ISSN 0021-9606. PMID 19334846.
- ↑ Onda, Ken; Li, Bin; Zhao, Jin; Jordan, Kenneth D.; Yang, Jinglong; Petek, Hrvoje (20 May 2005). "Wet Electrons at the H2O/TiO2(110) Surface". Science. 308 (5725): 1154–1158. Bibcode:2005Sci...308.1154O. doi:10.1126/science.1109366. PMID 15905397. S2CID 46147775.
- ↑ Feng, Min; Zhao, Jin; Petek, Hrvoje (18 April 2009). "Atomlike, hollow-core-bound molecular orbitals of C60". Science. 320 (5874): 359–362. Bibcode:2008Sci...320..359F. doi:10.1126/science.1155866. PMID 18420931. S2CID 7839410.
- ↑ Tan, Shijing; Argondizzo, Adam; Ren, Jindong; Liu, Liming; Zhao, Jin; Petek, Hrvoje (30 November 2017). "Plasmonic coupling at a metal/semiconductor interface". Nature Photonics. 11 (12): 806–812. Bibcode:2017NaPho..11..806T. doi:10.1038/s41566-017-0049-4. S2CID 125592128.
- ↑ "The Editor in Chief of Progress in Surface Science". Progress in Surface Science. Retrieved 2019-05-16.
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- ↑ "Hrvoje Petek, Senior Scientific Advisor". Institute for Molecular Science. Japan. Retrieved 17 May 2019.
- ↑ "ACS 2019 national award winners". ACS. Retrieved 2018-09-15.
- ↑ "Two Pitt Professors Named American Association for the Advancement of Science Fellows". University of Pittsburgh. Retrieved 2016-12-06.
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- ↑ "APS Fellow Archive". www.aps.org. Retrieved 2019-09-23.
- ↑ "Hrvoje Petek Receives Medal Following Alexander von Humboldt Lecture". Pittsburgh Quantum Institute. Retrieved 2019-09-23.
- ↑ "New Energy and Industrial Technology Development Organization". NEDO. Retrieved 2019-05-06.
