Size-dependence of the effective electron-phonon energy relaxation in hollow gold nanospheres

AbstractIn this paper the size-dependence of energy relaxation, which is induced by the electron-phonon (e-ph) interactions and the electron-surface (e-s) interactions in noble metal nanoparticles, is investigated. Then based on the analysis and the derivation of the e-s coupling constant in metal nanospheres, the formula of the effective electron-phonon coupling constant Geff of hollow gold nanospheres (HGNs) is deduced. Moreover, the correctness of the formulae gets proved by contrast analyses of the calculated Geff values and experimental values obtained from literature.

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THEORETICAL ASPECTS OF THE FIELD INDUCED SUPERCONDUCTIVITY IN POLYACENES AND C60

International Journal of Modern Physics B ◽

10.1142/s0217979202011299 ◽

2002 ◽

Vol 16 (11n12) ◽

pp. 1547-1551

Author(s):

S.-L. DRECHSLER ◽

G. PAASCH ◽

J. MÁLEK ◽

S. V. SHULGA ◽

H. ESCHRIG ◽

...

Keyword(s):

Tight Binding ◽

Band Structure Calculation ◽

Full Potential ◽

Coupling Constant ◽

Phonon Coupling ◽

Critical Temperatures ◽

Binding Model ◽

Electron Phonon Coupling ◽

Strong Coulomb ◽

Experimental Values

The electronic structure and the superconductivity in field-doped polyacenes are considered. Within a modified Thomas–Fermi approach for typical experimental values of the surface charge density the injected charge is confined to a monolayer. The electron–phonon coupling constant for internal modes λintra is estimated using the work of Devos and Lanoo (Ref. 4) and the density of states N(0) estimated from a 2D tight-binding model derived from a full potential LDA band structure calculation for bulk anthracene. The empirical values of the Coulomb pseudopotentials are significantly enhanced. The strong Coulomb interaction is considered as a key quantity which determines the large differences in the critical temperatures achieved for n-doped polyacenes and C 60.

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Ultrafast electron–phonon coupling in hollow gold nanospheres

Physical Chemistry Chemical Physics ◽

10.1039/c1cp22743b ◽

2011 ◽

Vol 13 (48) ◽

pp. 21585 ◽

Cited By ~ 23

Author(s):

Anne-Marie Dowgiallo ◽

Kenneth L. Knappenberger

Keyword(s):

Phonon Coupling ◽

Gold Nanospheres ◽

Hollow Gold Nanospheres ◽

Electron Phonon Coupling

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MAGNETOPOLARON IN A CYLINDRICAL QUANTUM DOT

International Journal of Nanoscience ◽

10.1142/s0219581x09006286 ◽

2009 ◽

Vol 08 (04n05) ◽

pp. 455-463 ◽

Cited By ~ 7

Author(s):

M. TCHOFFO ◽

L. C. FAI ◽

N. ISSOFA ◽

S. C. KENFACK ◽

J. T. DIFFO ◽

...

Keyword(s):

Magnetic Field ◽

Quantum Dot ◽

Longitudinal Direction ◽

Logarithmic Function ◽

Magnetic Field Effects ◽

Coupling Constant ◽

Phonon Coupling ◽

Cyclotron Radius ◽

Effective Electron ◽

Electron Phonon Coupling

We examine the magnetopolaron state in a cylindrical quantum dot with a transverse parabolic potential and a high rectangular potential well in the longitudinal direction. The quadratic dependence of the magnetopolaron energy versus Fröhlich electron–phonon coupling constant for different cyclotron radii and constant structure radius is modulated by a logarithmic function seems to depend on the Fröhlich coupling constant. The same law is seen in the case of magnetopolaron energy versus Fröhlich electron–phonon coupling constant for different structure radii and constant cyclotron radius. The energies are seen to be lifted in different fashions in the case of the structure and cyclotron radii. The high degrees of confinement (or high magnetic field) lead to an enhancement in the effective electron–phonon coupling that in turn brings about the possibility that in spite of weak polar coupling as in GaAS say, the polaron problem may also have strong-coupling counterparts arising from confinement or magnetic field effects. The polaron mass increases with increasing Fröhlich electron–phonon coupling constant. The dependence seems to be fourth-order law of the Fröhlich coupling constant modulated by a logarithmic function.

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