Zinc sulfide (ZnS) Fröhlich and exciton-phonon coupling constants cubic modification

The Davydov's soliton propagation in the linear polymer chain is analyzed numerically by solving the discrete equations of motion for exciton and phonon amplitudes. The main difference with respect to the results of continual approximation is that two exciton–phonon coupling constants influence separately the soliton behavior. Their influence is studied both in the ideal chain and the chain with single impurity.

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Electron-phonon Coupling in the 4T2g Excited Electron State of Cs2GeF6:Mn4+

Zeitschrift für Naturforschung A ◽

10.1515/zna-2005-1-209 ◽

2005 ◽

Vol 60 (1-2) ◽

pp. 54-60

Author(s):

N. M. Avram ◽

M. G. Brika

Keyword(s):

Energy Surface ◽

Normal Modes ◽

Coupling Constants ◽

Octahedral Complex ◽

Phonon Coupling ◽

Orbit Splitting ◽

Spin Orbit Splitting ◽

Electron Phonon Coupling ◽

Jahn Teller ◽

Jahn Teller Effect

In the present paper we report on an analysis of the fine structure of the first excited quartet 4T2g of Mn4+ ions which occupy the octahedral site in the Cs2GeF6 host crystal. The dynamic 4T2g⊗(eg+t2g) Jahn-Teller effect is considered in details, including the Ham effect of the reduction of the spin-orbit splitting and displacements of the ligands due to the combined effect of the a1g and eg normal modes of the [MnF6]2− octahedral complex. The electron-phonon coupling constants are evaluated using the experimental spectroscopic data. The value of the Jahn-Teller stabilization energy EJT = 438 cm−1 for the considered complex is estimated from both the Ham effect and the potential energy surface of the 4T2g excited state.

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Determination of the electron-phonon coupling constants from the experimental temperature dependences of superconducting gaps in MgB2

JETP Letters ◽

10.1134/s0021364014050129 ◽

2014 ◽

Vol 99 (5) ◽

pp. 295-302 ◽

Cited By ~ 14

Author(s):

S. A. Kuzmichev ◽

T. E. Kuzmicheva ◽

S. N. Tchesnokov

Keyword(s):

Coupling Constants ◽

Experimental Temperature ◽

Phonon Coupling ◽

Electron Phonon Coupling ◽

Temperature Dependences

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Electron–phonon coupling in conjugated polymers: Reference force field and transferable coupling constants for polyacetylene

The Journal of Chemical Physics ◽

10.1063/1.464684 ◽

1993 ◽

Vol 98 (9) ◽

pp. 7459-7465 ◽

Cited By ~ 41

Author(s):

Alberto Girlando ◽

Anna Painelli ◽

Z. G. Soos

Keyword(s):

Force Field ◽

Conjugated Polymers ◽

Coupling Constants ◽

Phonon Coupling ◽

Electron Phonon Coupling

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Influence of disorder strength on the superconducting mechanism of MgB2

Superconductor Science and Technology ◽

10.1088/1361-6668/ac392a ◽

2021 ◽

Author(s):

Jung Min Lee ◽

Soon-Gil Jung ◽

Younseok Han ◽

Tae-Ho Park ◽

Jae Kyung Jang ◽

...

Keyword(s):

Thin Films ◽

Ion Irradiation ◽

Electronic System ◽

Coupling Constants ◽

Disorder Strength ◽

Coupling Constant ◽

Phonon Coupling ◽

Normal State Resistivity ◽

Electron Phonon Coupling ◽

Effect Of Disorder

Abstract We investigate the effect of disorder on the superconducting mechanism of MgB2 thin films using low-energy ion irradiation. The c-axis lattice constant and T c of MgB2 thin films change systematically as the magnitude of disorder, which corresponds to the value of average displacements per atom (dpaavg ), increases. Here, dpaavg is controlled by the amount of irradiated ions. The dpaavg dependence of the electron-phonon coupling constants (λ) is estimated using the McMillan equation. For dpaavg ≤ 0.049, λ is linearly proportional to dpaavg . On the other hand, for dpaavg > 0.049, the T c of the disordered MgB2 deviates from the linear fitting curve, and insulating behavior is observed in the normal state resistivity. These results indicate that the superconducting mechanism of MgB2 can be changed by the electronic system caused by disorder strength affecting the electron-phonon coupling constant λ.

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