Raman scattering and X-ray diffraction study in Cu2GeSe3

Photoluminescence study of Cu2GeSe3 semiconductor compound has been performed as a function of excitation intensity at 15 K. All the emission lines observed have been identified. These are due to free‐to‐bound recombination from the conduction band to Cu vacancies and Cu on Ge antisite acceptor states, at 0.753 and 0.637 eV, located at about 65 and 180 meV above the top of valence band, respectively, whereas the line at 0.727 eV is due the recombination of an exciton bound to an ionized acceptor whose binding energy is of about 90 meV.

show abstract

“…44). This was confirmed by recent powder XRD analysis . Also, CGSe nanocrystals have been found to form in orthorhombic structure .…”

Section: Introductionsupporting

confidence: 73%

Photoluminescence Spectra of Cu₂GeSe₃ Orthorhombic Semiconductor Compound

Marcano

Pérez

Rincón

2017

Physica Status Solidi (b)

View full text Add to dashboard Cite

show abstract

“…For Cu 2 GeTe 3 , to the best of our knowledge, no Raman studies have been reported. However, since for the

C {normalu}_{2} {normalB}^{I V} {normalX}_{3}^{V I}

ternary compounds main Raman peaks observed are related to vibrations of the X VI anion , it is expected that Raman spectrum for Cu 2 SnTe 3 should be similar to that of Cu 2 GeTe 3 . Thus, lines at 123 and 142 cm −1 of the present spectrum which coincides with those of the main lines reported for Cu 2 SnTe 3 are tentatively assigned to Cu 2 GeTe 3 .…”

Section: Resultsmentioning

confidence: 99%

Structural characterization of the high‐temperature modification of the Cu₂ZnGeTe₄ quaternary semiconductor compound

Nieves

Delgado

Marcano

et al. 2016

Physica Status Solidi (b)

Self Cite

View full text Add to dashboard Cite

A combined study of the X-ray powder diffraction, differential thermal analysis, optical absorption, and Raman spectroscopy of the high-temperature modification of Cu 2 ZnGeTe 4 quaternary semiconductor, obtained by fast quenching from 820 K to ice water temperature, has been done. It has been found that this phase crystallizes in a tetragonal kesterite-type structure. From the analysis of the absorption coefficient spectra, the band gap energy of this material at room temperature has been found to be 1.49 eV. An optical transition from defect acceptor states to the conduction band is also observed below the fundamental absorption edge. Three strongest Raman lines observed at 116, 119, and 139 cm À1 have been assigned to the A-symmetry modes. Also, lines at 81, 89, 97, and 263 cm À1 tentatively ascribed as B or E-symmetry modes have been detected from the spectrum. The presence in this hightemperature modification of ZnTe and Cu 2 GeTe 3 secondary phases has been detected by both XRD and Raman spectroscopy.

show abstract

“…Also, the average frequency of the eight Raman modes observed in CGSe, weighted by the peak intensity of the lines, given in Ref. 26, is around 220 cm −1 (hν p0 ≈ 27 meV) as estimated by means of the expression i I i ν i / i I i . This frequency is also in good agreement with the value calculated above.…”

Section: Resultsmentioning

confidence: 95%

“…where hν p is the energy of the phonons associated with Urbach's tail and σ 0 a constant. Different values of hν p for the same material, some of them much higher than the highest optical mode observed in the vibrational spectra of each material, have been reported in ternary chalcopyrite [18,[20][21][22] and chalcopyrite-related structure compounds [23][24][25][26]. The existence of these unusually higher energy modes is explained by assuming that they are due to the structural disorder caused by the deviation from ideal molecularity and valence stoichiometry in the samples studied [18].…”

Section: Theorymentioning

confidence: 84%

See 1 more Smart Citation

Urbach’s tail in the absorption spectra of Cu2GeSe3 semiconducting compound

et al. 2018

View full text Add to dashboard Cite

In the present work we report on the analysis of the Urbach’s tail in pure and Mn-doped Cu2GeSe3 samples having small deviation from its ideal stoichiometry. It is found that the high values of the phonon energy hnp involved in the electrons/excitons-phonon interaction in the formation of this tail are due to structural disorder caused by deviation from ideal stoichiometry. Values of hnp for pure and doped samples were found to be 48, 60 and 81 meV, respectively, whereas the phonon energy for an entirely ordered Cu2GeSe3 sample was estimated to be about 25 meV.

show abstract

Raman scattering and X-ray diffraction study in Cu2GeSe3

Cited by 35 publications

References 18 publications

Photoluminescence Spectra of Cu₂GeSe₃ Orthorhombic Semiconductor Compound

Photoluminescence Spectra of Cu₂GeSe₃ Orthorhombic Semiconductor Compound

Structural characterization of the high‐temperature modification of the Cu₂ZnGeTe₄ quaternary semiconductor compound

Urbach’s tail in the absorption spectra of Cu2GeSe3 semiconducting compound

Contact Info

Product

Resources

About

Raman scattering and X-ray diffraction study in Cu2GeSe3

Cited by 35 publications

References 18 publications

Photoluminescence Spectra of Cu2GeSe3 Orthorhombic Semiconductor Compound

Photoluminescence Spectra of Cu2GeSe3 Orthorhombic Semiconductor Compound

Structural characterization of the high‐temperature modification of the Cu2ZnGeTe4 quaternary semiconductor compound

Urbach’s tail in the absorption spectra of Cu2GeSe3 semiconducting compound

Contact Info

Product

Resources

About

Photoluminescence Spectra of Cu₂GeSe₃ Orthorhombic Semiconductor Compound

Photoluminescence Spectra of Cu₂GeSe₃ Orthorhombic Semiconductor Compound

Structural characterization of the high‐temperature modification of the Cu₂ZnGeTe₄ quaternary semiconductor compound