Ballistic electrons

B. Eckhardt, Transition state theory for ballistic electrons, J. Phys. A 28, 3469 (1995). 

Zhong Z, Gabor NM, Sharping JE et al (2008) Terahertz time-domain measurement of ballistic electron resonance in a single-walled carbon nanotube. Nat Nanotechnol 3 201-205... 

Further advances will come by combination of STM with other forms of spectroscopy and scanning probe microscopy. One such emerging method that allows researchers to see beneath the surface of samples is ballistic electron emission microscopy (BEEM).159... 

BEEM BOMD Ballistic Electron Emission Microscopy Bohr-Oppenheimer Molecular Dynamics... 

Chaos does not only wreak havoc in otherwise orderly atomic spectra, it also provides a natural framework, indeed a common language, in which one can discuss such seemingly unrelated systems as, e.g., ballistic electrons in mesoscopic semiconductor structures, the hehum atom, and Rydberg atoms in strong external fields. All these systems have one feature in common their classical counterparts are chaotic. Chaos imprints its presence on their spectra and manifests itself in spectral features which are very similar for all these systems (universahty). 

At metal/semiconductor contacts the cone angle 6=5° since tan e= Va/ Vf, with Ejt, is the thermal velocity of electrons (10 cm s ) and Vf is the velocity of electrons at the Fermi surface in the metal (10 cm s ) [189]. In BEEM 6 should be even smaller since ballistic electrons have a greater kinetic energy than electrons in the metal. 

Fig. 2 shows the experimental results for the even SH component variation defined above, obtained for the films of 50 and 100 nm of Au. The value of the dropdown observed exceeded 5% of magnitude for the Au/Fe films. One can see the different type of the SH field deviation relaxation for two films of different thicknesses, which can be attributed to the larger path of the ballistic electrons transport in the case of 100 nm-Au film. The electron pulse scatters and broadens while propagating in Au, which affects the relaxation rate. The inset... 

Two-dimensional arrangements might be monolayers of clusters on a suitable substrate or two or more coupled ID arrays. While layers are accessible via self-assembly, LB, or electrodeposition, coupled arrays could be obtained by filling clusters into the parallel channels of a crystalline nanoporous solid. 2D networks of clusters might be precursors for simple neural networks, utilizing the Coulombic interaction between ballistic electrons in a 2D electron gas. This concept has been discussed by Naruse and in general introduces new possibilities for the interconnection approach in various fields, e.g. parallel processing and quantum functional devices. 

This combination of features might be useful in applications where high-electric field and high-frequency operations are essential [128]. The ballistic electronic properties of metallic SWCNTs lend this material to use as a contact to molecules. Calculations suggest that alignment of the Fermi level of m-SWCNTs and the energy levels of coimected molecules may enable the use of such systems in a new generation of nanoscale devices [129—131]. 

Gelloz B, Kanda T, Uchida T, Niibe M, Kojima A, Koshida N (2005a) Electroluminescence enhancement assisted with ballistic electron excitation in nanoerystalline silicon diodes. Jpn J Appl Phys Part 1 44(4B) 2676-2679... 

Key features of nanostructures that typically are exploited are a high surface area, a short solid state diffusion path, a high aspect ratio (ID materials), fast electron separation and transport, and fast switching of surface charges (inch oxidation state of the entire bulk nanostructure or its surface). Except for these conventional features, specific features to the nanoscale, namely quantum size effects, such as band-gap-widening or ballistic electron transport " may be the target of electrochemical processing. 

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