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Charging effects, quantized

Other metallic clusters that have been demonstrated to show the QDL effect are palladium [116, 117], silver [118] and copper [119]. Palladium MFCs capped with mixed monolayers of hexanethiolate/dodecanethiolate and ferrocene thiolate ligands are prepared in a manner similar to that employed for gold MFCs. The DPV studies exhibit a quantized charging effect but the current peaks are not as well defined as those observed for Au-MPCs. Capacitance values of the order of 0.35 aF are obtained, indicating smaller core sizes or thicker monolayer dielectrics [116]. [Pg.663]

These peculiarities of metal nanopartides do not, however, eliminate charging effects in them. Both, theoretical and experimental investigations have shown that the fundamental results of SET still hold true qualitatively. For example, the current-voltage characteristic of a double-barrier junction with a quantum dot (QD) possesses at low temperature, as well as the Coulomb staircase, a fine structure due to energy quantization inside the Q D. Nevertheless, the interpretation of these results is comphcated by the fact that the characteristic time RyC becomes as short as the characteristic time of the energy relaxation inside the QD, and consequently the... [Pg.410]

In the course of his research on electromagnetic waves Hertz discovered the photoelectric effect. He showed that for the metals he used as targets, incident radiation in the ultraviolet was required to release negative charges from the metal. Research by Philipp Lenard, Wilhelm Hallwachs, J. J. Thomson, and other physicists finally led Albert Einstein to his famous 1905 equation for the photoelectric effect, which includes the idea that electromagnetic energy is quantized in units of hv, where h is Planck s con-... [Pg.620]

Some years later a more thorough discussion of the motion of pairs of electrons in a metal was given by Cooper,7 as well as by Abrikosov8 and Gor kov,9 who emphasized that the effective charge in superconductivity is 2e, rather than e. The quantization of flux in units hc/2e in superconducting metals has been verified by direct experimental measurement of the magnetic moments induced in thin films.10 Cooper s discussion of the motion of electron pairs in interaction with phonons led to the development of the Bardeen-Cooper-Schrieffer (BCS) theory, which has introduced great clarification in the field of superconductivity.2... [Pg.825]

The size of the crystals formed in CD films is often small enough that quantum-size effects become apparent. The terms quantum size effect and size quantization are normally used to describe a material whose energy structure differs from that of the bulk material. As crystal (or, more generally, particle) size decreases, charges (electrons and holes) in the particles are constrained in an increasingly small volume. When the particle size becomes smaller than the Bohr diameter of the charges in the bulk material (between 2 and 20 nm for many ma-... [Pg.87]

The effective masses of electrons (md) and holes (m ) represent the masses that these charges appear to have when moving in the solid rather than in free space, and these vary from material to material. (In the size quantized regime, they can also vary with crystal size, particularly for small quantum dots, hence the limitations of the effective mass model). [Pg.352]

In order to calculate the spin-angular parts of matrix elements of the two-particle operator (1) with an arbitrary number of open shells, it is necessary to consider all possible distributions of shells upon which the second quantization operators are acting. In [2] they are found to be grouped into 42 different distributions, subdivided into 4 different classes. This also explains why operator (1) is written as the sum of four complex terms. The first term represents the case when all second-quantization operators act upon the same shell (distribution 1 in [2]), the second describes the situation when these operators act upon the two different shells (distributions 2-10), third and fourth are in charge of the interactions upon three and four shells respectively (distributions 11-18 and 19-42). Such expression is particularly convenient to take into account correlation effects, because it describes all possible superpositions of configurations for the case of two-electron operator. [Pg.441]

This is an introduction to the sort of process that may occur in 0(3>)b electrodynamics. In effect, the B 3 field produces quantum vortices that interact with electrons, as well as other charged particles, where these vortices are quantized states and exist as fluctuations in the QED vacuum. As mentioned earlier the dual of the B 3 field does not exist as an electric field. These quantum fluctuations are easily seen to be associated with the and E fields ... [Pg.448]

The main objection against the Bohr and Sommerfeld atomic models was the ad hoc definition of stationary states. Simply declaring these as quantum states offers no explanation for the failure of an accelerated charge to radiate energy. The quantization of neither energy nor angular momentum implies such an effect. [Pg.31]


See other pages where Charging effects, quantized is mentioned: [Pg.202]    [Pg.631]    [Pg.632]    [Pg.662]    [Pg.4]    [Pg.1301]    [Pg.95]    [Pg.144]    [Pg.344]    [Pg.487]    [Pg.69]    [Pg.169]    [Pg.182]    [Pg.267]    [Pg.286]    [Pg.287]    [Pg.164]    [Pg.248]    [Pg.176]    [Pg.112]    [Pg.174]    [Pg.344]    [Pg.2]    [Pg.120]    [Pg.248]    [Pg.728]    [Pg.753]    [Pg.199]    [Pg.629]    [Pg.11]    [Pg.66]    [Pg.157]    [Pg.275]    [Pg.276]    [Pg.182]    [Pg.154]   
See also in sourсe #XX -- [ Pg.662 ]




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Quantization

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Quantized

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