Structural and magneto-optical properties of PbO–Bi2O3–B2O3–Al(PO3)3 glasses.

• New boron-phosphate glass network was obtained by the introduction of Al(PO 3) 3 into boron oxide glass. • The structure of as-prepared glasses changed due to the reconstruction of glass network by [PO 4 units. • The transformation of glass network resulted in the redistribution of highly polarized ions and affecting the magneto-optical properties. • A new method to improve magneto-optical properties was proposed, instead of increasing the content of transition metal oxide and rare earth metal oxide. Herein, diamagnetic PbO–Bi 2 O 3 –B 2 O 3 –Al(PO 3) 3 glasses are prepared by melt-casting and the influence of phosphorus tetrahedral on the structure and optical properties of the glass has been systematically investigated. Compared to diamagnetic PbO–Bi 2 O 3 –B 2 O 3 (PBB) glasses, the original boron chain network has been replaced by the boron-phosphate structure. The metaphosphate forms [PO 4 units and expands the glass network, which leads to the decline of density and the increase of refractive index (up to ~2.423 @633 nm). The improvement of the magneto-optical properties performs in that the Verdet constant achieves 0.203 min/G cm at 633 nm and higher magneto-optical figure of merit displays a better optical performance than the diamagnetic glass without metaphosphate. [ABSTRACT FROM AUTHOR]