Temperature dependent raman and photoluminescence of an individual Sn-doped CdS branched nanostructure

Abstract

Temperature dependent Raman spectra and photoluminescence, as well the Raman mapping of different parts in an individual Sn-doped CdS comb-like nanostructure reveal that the stronger electron-phonon coupling exist at the trunk-branch junctions than other parts. The Huang-Rhys factor was calculated and further confirms that the strong electron-phonon correlation at the junction. The localized deformation from the Sn dopant in the lattice leads to strong electron-phonon coupling at the local junction, which is proved by the scanning transmission electron microscope and energy dispersion spectrum. Moreover, the lifetime of near-band-edge emission and deep-level emission drastically increase with decreasing temperature, which both relate to the localized electronphonon coupling and relaxation process. This work provides a clear description of the localized carrier correlation in the cross junction part of these branched nanostructures, which can be used to modulate the optoelectronic performance of micro/nanodevices.

Temperature Raman Studies of Freestanding and Flexible Thin Films of CdS‐doped PVDF

“…f. As reported earlier at low temperature the hump shifts towards the higher wavenumber due to freezing of lattice . The low intensity of 1LO mode also stems out of the fact that CdS is used as a dopant in the polymer matrix.…”

“…The shift in the peaks seems to follow a nearly linear fit. The freezing of crystal lattice at low temperature leads to reduction in electron–phonon coupling hence resulting in the blue shift . Figure e shows the full range spectra recorded at different temperatures ranging from 80 K to 295 K for CdS/PVDF film.…”

“…For conduction of heat in a laminar surface, thermal conductivity can be written as where, k is the thermal conductivity, T the absolute temperature and d σ a small area element. As reported by Balandin et al and Sahoo et al, the thermal conductivity is calculated as . where ΔP the laser power difference and h is is the thickness of the film. can be calculated from Eq .…”

Dual-Color Lasing Lines from EMPs in Diluted Magnetic Semiconductor CdS:NiI Structure

“…On the basis of the above-mentioned group theory explanation, the observed five modes are attributed to 1TO, E 1 (TO), E 2 H , 1LO, and 2LO phonon modes of CdS [36, 37]. All the modes are listed in ; most of the modes redshifted as compared to respective modes of pure CdS NB, confirming the successful incorporation of Ni ions or halogen ions into CdS lattice [38].…”

Position‐Sensitive Array Photodetector Based on Comb‐Like CdS Nanostructure with Cone‐Shape Branches

“…Upon dark condition, the conductance gradually increases with the ambient temperature rising from 80 to 300 K. The reason is that the phonon‐assisted transportation of the free carriers becomes weak at low temperature. Moreover, the electron–phonon coupling will be reduced due to the phonon becoming much weaker at low temperature, which has been proven by the temperature‐dependent Raman spectrum in our previous work . At high temperature, the thermionic emission plays a major role, so that the conductance becomes larger.…”