Nordheim

While field ion microscopy has provided an effective means to visualize surface atoms and adsorbates, field emission is the preferred technique for measurement of the energetic properties of the surface. The effect of an applied field on the rate of electron emission was described by Fowler and Nordheim [65] and is shown schematically in Fig. Vlll 5. In the absence of a field, a barrier corresponding to the thermionic work function, prevents electrons from escaping from the Fermi level. An applied field, reduces this barrier to 4> - F, where the potential V decreases linearly with distance according to V = xF. Quantum-mechanical tunneling is now possible through this finite barrier, and the solufion for an electron in a finite potential box gives... 

Fig. 8. Band-to-band tunneling in a semiconductor where the triangular barrier leads to Fowler-Nordheim tunneling (33).

Fig. 13. Electric-field dependence of the emission current obtained for a carefully aligned MWCNT film [38], Inset Fowler-Nordheim plot, where y is the field-enhancement factor.

Rich, A., Nordheim, A., and Wang, A. H.-J., 1984. The chemi.stry and biology of left-handed Z-DNA. Annual Review of Biochemistry 53 791-846. 

Fluctuating Gap Model Fowler-Nordheim fluorine-doped tin dioxide full width at half maximum geminate pair... 

The field-induced tunneling across a potential barrier can be described using the Fowler-Nordheim equation [79] ... 

However, the values for the current, which are obtained using the Fowler-Nordheim equation with the actual device parameters, are several orders of magnitude [81, 82) higher than the values for the measured current in real devices. 

For the same the single layer devices based on Alq3, Peyghambarian et al. [83] found that the 1/V characteristics can also be described by an SCL current flow in the low cu ire lit regime. However, in the low current regime the 1/V characteristics can be qualitatively modeled by the Fowler-Nordheim equation (even if, quantitatively, the real device current differs from the calculated by seven orders of magnitude) [83] and thermionic emission ]78]. 

Lafer EM, Valle RP, Moller A, Nordheim A, Schur PH, Rich A, Stollar BD (1983) J Clin Invest 71 314... 

RH Fowler and L Nordheim, Electron emission in intense electric fields, Proc. R. Soc. Lond., 119 173-181, 1928. 

Fowler-Nordheim tunneling of, 22 258 in HBTs, 22 167-168 Moore s law and device scaling and, 22 254 in RTDs, 22 170-171 in semiconducting silicon, 22 485-486 in semiconductors, 22 233, 237-239 in SETs, 22 171-172 in single layer OLEDs, 22 215-216 in spinel ferrites, 11 60-61 in the superconducting state, 23 804 Electron spectrometer system, components of, 24 100-101... 

In the virtual-crystal approximation (VCA) (Nordheim 1931), the site energy of an alloy atom is taken to be... 

Fig. 10.19 (a) Current-voltage characteristic of the cold cathode according to the circuit shown in Fig. 10.18. (b) A Fowler-Nordheim... 

Field emission is the emission of electrons from a solid under an intense electric field, usually at ambient temperatures. It occurs by the quantum mechanical tunneling of electrons through a potential barrier (Fig. 13.1). This leads to an exponential dependence of emission current density J on the local electric field, as given by the Fowler Nordheim equation,... 

CO adsorbed Pd/Al Oj, 37 69-70 diffuse reflectance spectroscopy, 34 14 Fowler-Nordheim equation, 21 72 Fraction exposed, of total metal atoms definition, 36 72-73... 

Janknecht R, Nordheim A (1996) MAP kinase-dependent transcriptional coactivation by Elk-1 and its cofactor CBP. Biochem Biophys Res Commun 228 831-837 Jason LJ, Moore SC, Lewis JD, Lindsey G, Ausio J (2002) Histone ubiquitination a tagging tail unfolds Bioessays 24, 166-174... 

Eltun, R., Fugleherg, O. and O. Nordheim (1996). The Apelsvoll cropping system experiment Vll. Runoff losses of soil particles, phosphorus, potassium, magnesium, calcium and sulphur. Norwegian Journal of Agricultural Sciences 10 371-384. 

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