Optical properties of gapped graphene structure in the presence of electron-phonon interaction: A full band approach

2016 ◽  
Vol 100 ◽  
pp. 474-482 ◽  
Author(s):  
Hamed Rezania ◽  
Parisa Zare
Keyword(s):  
Optical Properties ◽  
Phonon Interaction ◽  
Gapped Graphene ◽  
Electron Phonon Interaction ◽  
Full Band

Electron–phonon interaction influence on optical properties of parallelogram quantum wires

2014 ◽  
Vol 28 (22) ◽  
pp. 1450142 ◽  
Author(s):  
H. Bahramiyan ◽  
R. Khordad ◽  
H. Azari
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Quantum Wire ◽  
Quantum Wires ◽  
Energy Levels ◽  
Moment Matrix ◽  
Absorption Coefficients ◽  
Phonon Interaction ◽  
Electron Phonon Interaction ◽  
Index Changes

In the present work, we have studied the effect of electron–phonon (e–p) interaction on optical properties of a GaAs quantum wire with parallelogram cross-section. For this goal, we have calculated refractive index changes and absorption coefficients by using compact-density-matrix approach and iterative method. The results show that the refractive index changes and absorption coefficients are obviously increased and the peak positions shift toward higher energies after considering the e–p interaction. We have also studied polaronic effect on electric dipole moment matrix elements and the energy levels for different quantum wire sizes. We have found that the line-width of absorption coefficients and refractive index changes is approximately constant after considering e–p interaction.

MAGNETIC AND OPTICAL PROPERTIES OF SODIUM CLUSTERS IN ZEOLITE LTA

1996 ◽  
Vol 03 (01) ◽  
pp. 717-720 ◽  
Author(s):  
TETSUYA KODAIRA ◽  
YASUO NOZUE ◽  
SATOSHI OHWASHI ◽  
NOZOMU TOGASHI ◽  
OSAMU TERASAKI
Keyword(s):  
Optical Properties ◽  
Singlet State ◽  
Reflection Spectra ◽  
Phonon Interaction ◽  
Magnetic Susceptibilities ◽  
Electron Phonon Interaction ◽  
Optical Reflection ◽  
Sodium Clusters ◽  
Zeolite Lta ◽  
Highly Loaded

Cationic Na clusters are formed in the α and β cages of Na-form LTA by incorporating Na atoms from vapor. The maximum number of Na atoms incorporated is 4.9 per unit cell. Ac magnetic susceptibilities and optical reflection spectra are measured as a function of Na loading density. Na clusters show diamagnetism independent of Na loading density while K clusters in K-LTA and Rb clusters in Rb-LTA show ferromagnetism at certain loading densities. All Na clusters contain therefore an even number of the electrons, which are supplied from 3s-electrons of the guest Na atoms, irrespective of the cages they are formed. The electron-phonon interaction plays an important role in stabilizing the singlet state. In the reflection spectra of highly loaded sample, a strong band is observed at 1.95 eV. An oscillator strength of this band exceeds unity per cluster by a great deal. This band is assigned to surface-plasmon-like excitation of Na cluster formed in α cage.

scholarly journals Influence of chemical composition and doping on optical properties of thallium selenide layers prepared by adsorption/diffusion method

Chemija ◽  
2021 ◽  
Vol 32 (2) ◽  
Author(s):  
Linas Samardokas ◽  
Remigijus Ivanauskas ◽  
Skirma Žalenkienė ◽  
Algimantas Ivanauskas
Keyword(s):  
Optical Properties ◽  
Precursor Solution ◽  
Molar Ratio ◽  
Diffusion Method ◽  
Chemical Compositions ◽  
Band Tail ◽  
Phonon Interaction ◽  
Electron Phonon Interaction ◽  
Eds Analysis ◽  
Thallium Selenide

In this work, we investigated the formation of Tl-Se layers followed by doping with metal cations. A two-stage adsorption/diffusion process used to form Tl-Se layers involves (a) selenization in potassium selenotrithionate solution followed by (b) treatment with Tl+ precursor solutions. These layers have been successfully doped with Cu+/Cu2+, Ga3+ and Ag+ cations using a cation exchange reaction. The resulting chemical compositions of Tl-Se and Tl-M-Se (M = Cu, Ga, Ag) layers were investigated using the EDS and AAS methods. The bulk elemental composition and the Tl/Se molar ratio of the Tl-Se layers varied with the concentration of the Tl+ precursor solution, the exposure time in the Tl+ precursor solution, and the form of the Tl+ in the solution, whereas the EDS analysis showed that the surface was slightly enriched in thallium. The optical properties of the formed layers were studied. These layers were identified using room temperature reflection spectrum, the values of absorption edge, bandgap (Eg), band tail width (Urbach energy, EU) of the localised states, Steepness parameter (σ) and electron–phonon interaction (Ee-p).

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