Optical energy gaps of In2−x Ga x S3 thin films prepared by spray pyrolysis

Optically decomposed near-band-edge structure and excitonic transitions in Ga2S3

“…A gold-doped chalcogenide glass containing the Ga 2 S 3 nanocrystals can be applied in the third-order nonlinear optics17. Ga 2 S 3 is a wide-band-gap semiconductor, however, to date, discrepant values of band gaps ranging from 2.5 to 3.4 eV have ever been found in the literatures1819. This result is owing to the uncertainty on the crystal quality and the lack of knowledge to the optically decomposed experimental band-edge structure of Ga 2 S 3 .…”

Structural, vibrational and electronic properties of α′-Ga2S3 under compression

“…The modes of the highfrequency region exhibit higher pressure coefficients than in the low-frequency region (see Table S1). It must be noticed that the theoretical mode frequencies in the high-frequency range underestimate those observed experimentally, mainly above 325 cm -1 from the A'' (11) to the A' LO (13) modes (Figure 7). Moreover, it can be noticed that, in general, the modes at the lower part of the high-frequency region show larger pressure coefficients than those at the high part of the high-frequency region and are more separated at 0 (162 cm -1 ) than at 12 GPa (135 cm -1 ).…”

“…20,25,78,90 In this region, we consider that the theoretically predicted A'' (7), A'' (9), A'' (10), A'' (12), A'' (14) modes have not been experimentally observed either in this work or in previous ones. Instead, we have tentatively assigned the LO counterparts of the A' (8), A'' (11), A' (11) and A' (13) modes in view of the mismatch between their pressure coefficients with those theoretically predicted and the higher frequencies observed. The modes of the highfrequency region exhibit higher pressure coefficients than in the low-frequency region (see Table S1).…”

“…216) phases have a good optical transparency in the IR region and large NLO effects, with SHGs and LIDTs competitive with commercial NLO materials, like KTiOPO 4 and AgGaS 2 . In a wider perspective of the optoelectronic industry, Ga 2 S 3 is a wide-band semiconductor (2.5-3.4 eV) 12, 13 suitable for a wealth of applications, such as emitters from near IR to blue region, 14-17 UV optical absorbers, 18 Terahertz receivers, 19-21 photovoltaic devices, 22, 23 gas sensors, 24, 25 micro-tunable lasers, 26 and fluorescent probe materials. 27 All the above applications reveal the great versatility of Ga 2 S 3 and open exciting prospects for inexpensive, non-toxic, and abundant-element-based devices.…”

Optical and Photoelectric Properties of Planar Structures Obtained by Thermal Annealing of Ga2S3 Plates in Zn Vapors

“…The absorption spectra measured with unpolarized light have two slopes that are determined by the specific structure of Ga 2 S 3 compound. The band gap of this compound, determined from photoconductivity and absorption spectra, varies form 2.5 up to 3.4 eV.…”