Photoluminescence of layered semiconductor GaS doped with Mn

Abstract

PACS 71.55. Ht, 78.55.Hx Manganese (Mn)-doped GaS single crystals were grown by the Bridgman technique. Radiative recombination mechanisms have been investigated using photoluminescence (PL) measurement. The PL spectrum (at 77 K) related to the impurity level is dominated by the new emission band at 2.002 eV. The temperature dependences of the PL intensity, peak energy, and full width at half-maximum are characterized by the recombination mechanism of the configurational coordinate model. It was found that the 2.002 eV emission band is related to the acceptor -vacancy complex center. Moreover, the concentration of the defect is very high in the Mn-doped GaS.

Vapor–Liquid–Solid Growth and Optoelectronics of Gallium Sulfide van der Waals Nanowires

“…Significant emission extends in a tail to longer wavelengths. Comparing with reported absorption measurements that give an indirect bandgap of GaS of 2.53 eV ( T = 300 K) , and 2.5–2.6 eV ( T = 77 K), as well as our EELS results showing E g = 2.65 eV for (few nm) thin single type (i) nanowires (Figure ), we can assign the strong CL emission at ∼2.58 eV to band-edge luminescence. The linescan of Figure (c) shows other notable features.…”

“…Single nanowire absorption measurements by EELS (Figure 6(a−c)) show a characteristic energy loss onsetassociated with interband transitions across the fundamental bandgapat E g = 2.65 eV, close to the previously reported bandgap of GaS. 37,38 Features between 3 and 10 eV are likely associated with special points in the GaS dielectric function seen previously, 39,40 while the peak at ∼17 eV has been explained by an excitation of the GaS bulk plasmon. 8,41 At low energy (in the gap region), the spectra show structure with intensity above the noise level whose energy coincides with emission features observed in CL (see below), i.e., which may be associated with losses due to transitions between gap states.…”

Characteristics of p-type Mg-doped GaS and GaSe nanosheets

“…It is well known that impurity states play an important role in the semiconducting optoelectronic devices. [17][18][19][20][21] Based on previous studies, Mg doping in a semiconductor is common in particular for GaN-based semiconductors to achieve p-type conductivity. 22,23 Moreover, the capability of achieving p-type doping in a GaN semiconductor has led to rapid development of the III-Nitride semiconductor light-emitting diodes (LED) technology by improving the internal quantum efficiency 24,25 and current injection efficiency in LEDs.…”

Radiative transitions of layered semiconductor GaS doped with P

“…The variation of indirect band gap energy E g of GaS as a function of temperature is also indicated for comparison in the figure. We evaluated E g from the bound exciton peak energy [12]. The values of 14 meV for binding energy and 10 meV for phonon energy were used in the calculation [5].…”

“…It is found that the deep recombination levels due to Cu atoms are localized at 1.23 and 1.48 eV below the conduction band. The 2.002 eV emission band was observed in the PL spectrum of Mn-doped pGaS [12]. This emission band is related to the acceptor-vacancy complex center and is caused by the recombination mechanism of the CC model.…”