Luminescent spectra of PbI2 single crystals doped by 3d-metal impurities

Excitation intensity and temperature‐dependent photoluminescence and optical absorption in Tl4Ga3InSe8 layered crystals

“…Our analysis reveals that the peak energy position changes with laser excitation intensity (blue shift). The behavior of the emission band is in agreement with the idea of inhomogenously distributed donor-acceptor pairs for which increasing laser excitation intensity leads to blue shift of the band by exciting more pairs that are closely spaced [10,11]. A careful inspection of the data shows that the emission band maximum slightly shifts towards higher energies (∆E p = 36 meV) with increasing excitation laser intensities from 0.…”

“…The observed emission band has asymmetrical Gaussian line shape and centered at 652 nm (1.90 eV) at T = 17 K. As seen from figure 3, emission band changes its peak position, full-width at half-maximum (FWHM) and intensity as a function of the sample temperature: the peak position shows several degrees of red shift with increasing temperature; the FWHM increases and the peak intensity decreases as temperature is increased. The FWHM rises from 0.09 to 0.12 eV with increasing temperature in the range of 17-68 K. Some features of the observed photoluminescence may be caused by a contribution of low-frequency interlayer vibrations [11]. Inset of figure 4 illustrates the shift of the peak energy to lower energies with increasing temperature.…”

Comparative study of crystal field effects for Ni2+ ion in LiGa5O8, MgF2 and AgCl crystals

“…Comparison of the Racah parameters for Ni 2+ in crystals ( series. These results which emphasized the specific role of the Ni ions doped in the title crystals could be added to that of paper [42] which has been observed during investigations of the spectra for Ni doped highly anisotropic crystals.…”

Effect of indium intercalation on various properties of MoSe2 single crystals

“…The decrease in the band gap may be because of the impurity levels introduced due to the addition of indium in MoSe 2 [4]. One of a possible mechanism determining the features of the energy bands may be caused by inter-layer lowenergy membrane rigid phonon modes, it was demonstrated by Rybak et al [16].…”