Design, Growth, and Characterization of High Verdet Constant Magneto-Optical Crystal in Cubic Oxide System Tb₂O₃/Y₂O₃/ZrO₂ Crystal with Enhanced Laser-Induced Damage Threshold

Abstract

Magneto-optical (M-O) crystals, with their large Faraday effects, low absorption coefficients, and high magnetic permeabilities, are widely used in the fields of optical modulators, isolators, phase shifters, optical switches, optical storage devices, optical displays, and laser gyroscopes. However, the commercialized terbium gallium garnet crystal has a low Verdet constant of 39−42 rad•m −1 •T −1 at 1064 nm and a laser-induced damage threshold of 1.14 GW/cm 2 (10 ns at 1064 nm), making it unable to meet the requirements of high-power devices. Based on the theoretical derivation of the Verdet constant, the critical factor that affects the Tb 3+ -doped Verdet constant is the number of Tb 3+ ions per unit volume N. Herein, we explore the new M-O crystal in a cubic oxide system with solid-phase sintering powder samples. By analyzing crystal structure and spectrum, calculated theoretical results indicate that the cubic oxide system Tb 2 O 3 /Y 2 O 3 /ZrO 2 crystals have a large Verdet constant. The optimal component of TYZ-1 is grown by the laser floating zone method. The theoretical calculation is consistent with the experimental result of 227 rad•m −1 •T −1 at 633 nm. Verifying the scientificity and rationality of the evaluation scheme was accomplished through experimentation. This work proposes a scheme for evaluating potential M-O crystals. We believe that this work will promote the exploration and development of M-O crystals.