Quantitative analysis of YIG, YFeO₃ and Fe₃O₄ in LHPG-grown YIG rods

The use of higher pulling rates in the laser heated pedestal growth (LHPG) method will cause the YIG (Y₃Fe₅O₁₂, yttrium iron garnet) crystals thus grown to contain YFeO₃, YIG and iron oxides due to rapid solidification. In the experiment, a Verwey transition, the distinctive magnetic property of magnetite, was observed near 107 K in the grown YIG rods using a super-conducting quantum interference device (SQUID) magnetometer. Moreover, the standard relationships between the YIG and YFeO₃ weight ratios and the primary diffraction-intensity ratios of the YIG (420) and YFeO₃ (121) peaks were obtained from the XRD data by indexing the powders with their specific ratios. We also derived the weight ratios of the three magnetic compounds in the grown rods, via measuring the saturation magnetizations. From the experimental results, the iron oxide in the grown rods is also confirmed to be magnetite. This is a good analytical technique for quantifying the magnetic compounds in a material.