Optical properties of GaSe1−xSx series layered semiconductors grown by vertical Bridgman method

Crystal structure and electronic structure of GaSe1−xSx series layered solids

“…A 1 is the direct band-gap transition for GaSe 1Àx S x (0pxp0:5). The energy variations of A 1 present nearly parallel composition dependence with respect to the sulfur change at 15 and 300 K. The compositional dependence of A 1 at 300 K is in good agreements with the previously obtained result by opticalabsorption measurements[26].…”

“…3(a) and (b) simultaneously demonstrates an energy blue shift behavior with respect to the increase of the S compositions. A 1 feature is a direct band-gap transition for GaSe 1Àx S x (0pxp0:5) series [26], which presents in a lower-energy value and a broader-lineshape character at 300 K than those at 15 K. For gallium sulfide, the sharp line feature A 1 do not clearly resolved in the PzR spectrum of 300 K but it instead of a much broader feature presented near the band-edge. The broader line feature also shows quite flat below 3 eV at 15 K. This result verifies that the GaS compound is an indirect band-gap material in which the scattering phonon and the light resonance between the layers tend to broaden the spectral line feature near the indirect gap at room temperature.…”

Characterization of As2(Se1−xSx)3 series glass system

“…The values are obviously larger than that of the crystalline semiconductors [25,27,28]. In general, as a crystal with good quality, the broadening parameter is in the order of tens of meV [27].…”

Characterization of Ge(Se1−xSx)2 series layered crystals grown by vertical Bridgman method

“…3, respectively). However, the values of broadening parameter obtained from TR for Ge(Se 1Àx S x ) 2 (0pxp1) are much larger that of the other layered structure semiconductors [22][23][24], The line shape of the TR spectrum depends on several effects, such as alloy scattering, electron-electron interaction, electron-phonon interaction, impurity, dislocation, etc. In general, as a crystal with good quality, the broadening parameter is in the order of tens of meV [23].…”