Nonthermal electron

Hot electron spin transistors are hybrid metal/semiconductor devices that rely on spin-dependent transport of hot (nonthermalized) electrons rather than electrons near the Fermi level. The spin-valve transistor (SVT) was the first example of this new class of spintronic devices [128, 129], It has a three-terminal structure consisting of a metallic spin-valve base that is sandwiched between two semiconductor substrates, serving as the emitter and the collector, respectively. The electrons in this device are transported perpendicular to the spin-valve layers at energies just above the collector Schottky barrier height. 

Bauer, C., Abid, J.P., Fermin, D. and Girault, H.H. (2004) Ultrafast chemical interface scattering as an additional decay channel for nascent nonthermal electrons in small metal nanoparticles. J. Chem. Phys., 120, 9302-9315. 

AA(/iv) is the change in absorbance as a function of the photon energy hv. NT and Th represent the nonthermalized and thermalized states, is the time constant for the electron-phonon interactions of the thermahzed electron distribution and is the internal electron thermalization time. is the decay time of the nonthermal electron population. Note that t, h is shorter than t,h because the nonthermahzed electron distribution interacts with the lattice during the thermalization process. 

Van de Laagemaat J, Prank AJ (2001) Nonthermalized electron transport in dye sensitized nanociystalline Ti02 films. J Phys Chem C 105 11194—20005... 

The observations of complex dynamics associated with electron-stimulated desorption or desorption driven by resonant excitation to repulsive electronic states are not unexpected. Their similarity to the dynamics observed in the visible and near-infrared LID illustrate the need for a closer investigation of the physical relaxation mechanisms of low energy electron/hole pairs in metals. When the time frame for reaction has been compressed to that of the 10 s laser pulse, many thermal processes will not effectively compete with the effects of transient low energy electrons or nonthermal phonons. It is these relaxation channels which might both play an important role in the physical or chemical processes driven by laser irradiation of surfaces, and provide dramatic insight into subtle details of molecule-surface dynamics. 

Thermal and Nonthermal Impact on Electrical and Electronic Equipment... 

A striking feature of the ILs is their low vapor pressure. This, on the other hand, is a factor hampering their investigation by MS. For example, a technique like electron impact (El) MS, based on thermal evaporation of the sample prior to ionization of the vaporized analyte by collision with an electron beam, has only rarely been applied for the analysis of this class of compounds. In contrast, nonthermal ionization methods, like fast atom bombardment (FAB), secondary ion mass spectrometry (SIMS), atmospheric pressure chemical ionization (APCI), ESI, and MALDI suit better for this purpose. Measurement on the atomic level after burning the sample in a hot plasma (up to 8000°C), as realized in inductively coupled plasma (ICP) MS, has up to now only rarely been applied in the field of IE (characterization of gold particles dissolved in IE [1]). This method will potentially attract more interest in the future, especially, when the coupling of this method with chromatographic separations becomes a routine method. 

As nonthermal plasma is a mixture of electrons, highly excited atoms and molecules, ions, radicals, photons, and so on, its chemistry is extremely complex, and highly selective products should not be expected via plasma chemistry. The basic reactions for controlling both the direction and reaction rate of plasma C02 utilization can be summarized as follows (here, A and B represent atoms, A2 and B2 molecules, e represents an electron, M is a temporary collision partner, and S represents a solid surface site. The excited species is indicated by an asterisk). 

Electric arc processes have been given a new lease on fife in the guise of plasma reactors, especially those involving cold, or nonthermal plasmas, with electron temperatures of I (E-IO5 K and gas temperatures of 102-103 K. Plasmas of this kind can be used to activate and functionalize inert molecules, but usually with only poor selectivities and low energy yields ( 0.01 mol/kWh ). The use of catalytic additives may offer some potential for improvement, but reactive plasma processes will probably remain restricted to a few specific applications. 

Barnes, F. S. Hu, C.-L. J. Model for some nonthermal effects of radio and microwave fields on biological membranes. Inst. Electrical Electronics Engineers, Trans. Microwave Theory and Techniques 1977, 25, 742-746. 

Nonthermal effects may result from the possible interactions between RF fields and the various components of the biological material. Established effects include (1) The interference of radio frequencies with cardiac pacemakers is possible, however, new models of pacemakers are currently equipped with electronic filters making them immune to fields from... 

---