Erbium ions oscillator strength and emission enhancement in antimony phosphate amorphous matrix

Abstract For the first time we report the Er 3 + ions concentration dependent physical, absorption and emission properties of melt quench synthesized antimony glass having composition (60 − x )Sb 2 O 3 –35P 2 O 5 –5MgO– x Er 2 O 3 (0.1 ≤ x ≤ 0.9 mol.%). Transparent glass samples having light yellow and deep pink colors are obtained. Glass density varied between 4.4 and 4.46 g/cm 3 as the Er 2 O 3 contents are increased. Glass with 0.3 mol.% of Er 2 O 3 revealed the highest density, lowest band gap energy, and maximum refractive index. UV–Vis–NIR spectra exhibited ten absorption bands accompanied by peak shift. Bonding of Er 3 + ions with ligands is found to alter from covalent to ionic character. Oscillator strength followed the trend of 2 H 11/2 > 4 G 11/2 , 4 G 9/2 > 4 F 9/2 > 4 I 13/2 > 4 F 7/2 > 4 I 11/2 > 4 F 5/2 , 4 F 3/2 > 4 I 9/2 > 4 S 3/2 . Room temperature emission spectra under 380 nm excitations comprised of intense (centered at 481.5, 457.5, 444, 438, 431, 421, and 410.5 nm) and weak (centered at 746.5, 538, 528.5, and 506 nm) peaks. Emission peaks revealed intensity enhancement with increasing concentration of Er 2 O 3 . The enhancement in oscillator strength for 4 G 11/2 , 4 G 9/2 states absorption, the high intensity of emission band in the blue region and large refractive index (2.28) makes these glasses prospective for down-conversion solid state violet and blue lasers as well as other photonic devices.