Optimizing pyroelectric x-ray detectors for synchrotron applications

This study presents a comprehensive investigation of pyroelectric detectors for high-energy x-ray detection. We compare three high-performance pyroelectric materials (LiTaO₃, LiNbO₃, and triglycine sulfate) in two geometries, thermally coupled and uncoupled, and contrasting current with conventional voltage amplifier designs. The results obtained using 17 keV synchrotron radiation demonstrate that current amplification significantly outperforms voltage follower configurations, achieving responsivity values of up to 10⁵ V/W with substantially improved signal-to-noise ratios. Of the three materials tested, triglycine sulfate exhibits superior sensitivity when used in thicker formats (specific detectivity D* ∼ 7.60 × 10⁷ cm Hz^1/2 W⁻¹), although LiTaO₃ offers better thermal stability for practical applications. Further optimization through thickness reduction of LiTaO₃ crystals in the range of 500–100 μm yielded substantial improvements in D*, with the thinnest crystals achieving D* values of ∼1.1 × 10⁸ cm Hz^1/2 W⁻¹ in uncoupled geometry, which maximizes thermal isolation and temperature rise per unit-absorbed power. These results validate our theoretical models, which predict performance enhancements through optimal thermal management and amplification strategies. This establishes new benchmarks for pyroelectric-based x-ray detection.