AgGaSe ₂ at High Pressure: Optical Absorption, Single Crystal X‐Ray Diffraction and Electronic Structure Calculations

Optical absorption and electron-nuclear double resonance study of Ni+ions in AgGaSe2crystals

“…These investigators were unable to make a precise identification of the responsible defect, but they did suggest that it was perhaps associated with deviations from stoichiometry. In a subsequent study, Halliburton et al [5] made a direct analogy to earlier work by Kaufmann [6] on AgGaS 2 and assigned the 2.2 µm absorption band in AgGaSe 2 to Ni + (3d 9 ) impurities that were unintentionally present in the crystals. More recently, a theoretical investigation of the g factors and hyperfine parameters of Ni + ions in AgGaS 2 and AgGaSe 2 has been reported [7].…”

Optical absorption and photoreflectance spectroscopy of the single-crystalline chalcopyrite semiconductor AgGaSe2

“…The fact suggests that AgGaSe 2 is a direct-bandgap semiconductor, in agreement with those reported in the literature. 12,13,[15][16][17][18][19][20][21][22][24][25][26] As easily understood from Fig. 1, the optical absorption spectra for AgGaSe 2 exhibit unique temperature dependence.…”

“…Although the material has been the subject of many research efforts, many fundamental properties are not sufficiently evaluated or are even unknown. 9 The optical properties of AgGaSe 2 have been studied using various techniques, such as far-infrared (IR) reflectivity, 10 near-IR-ultraviolet reflectivity, [11][12][13][14][15] optical absorption, [16][17][18][19][20][21][22][23][24][25][26] photoluminescence (PL), 11,19,[27][28][29][30][31][32][33] photoconductivity, [34][35][36][37] cathodoluminescence, 38 spectroscopic ellipsometry (SE), 39 electroreflectance (ER), 16 and photoreflectance (PR). 21 Most of these studies were carried out on polycrystalline AgGaSe 2 samples.…”

Optical constants and electronic energy-band structure of AgGaSe2

“…8,9) Although the material has been the subject of many research efforts, many of its fundamental properties are not sufficiently evaluated or are even unknown. 10) The optical properties of AgGaSe 2 have been studied using various techniques, such as those using far-infrared (IR) reflectivity, 11) near-IR-ultraviolet reflectivity, [12][13][14][15][16] optical absorption, [17][18][19][20][21][22][23][24][25][26][27][28] photoluminescence (PL), 12,20,[29][30][31][32][33][34][35] photoconductivity, [36][37][38][39] cathodoluminescence, 40) spectroscopic ellipsometry, 41) electroreflectance (ER), 17) and photoreflectance (PR). 22,28) However, little is known about the optical constants of AgGaSe 2 .…”