Methylammonium Lead Tribromide Single Crystal Detectors towards Robust Gamma-Ray Photon Sensing

Journal Article · 29 March 2020 · Advanced Optical Materials

DOI: https://doi.org/10.1002/adom.202000233 · OSTI ID:1630883

Tisdale, Jeremy Tyler  ^[1]; Yoho, Michael D. ^[1]; Tsai, Hsinhan  ^[1]; Shrestha, Shreetu  ^[1]; Fernando, Kasun ^[1]; Baldwin, Jon Kevin Scott  ^[1]; Tretiak, Sergei  ^[1]; Vo, Duc Ta  ^[1]; Nie, Wanyi  ^[1]

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1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

In recent years, hybrid perovskite single crystalline solid-state detectors have shown promise in γ-ray spectroscopy. Here, the γ-ray photon induced electrical pulses are investigated, which are produced by perovskite solid-state detectors made with the commonly used methylammonium lead tribromide crystals with chlorine incorporation. Under low electric field detector operation, slow pulses generated by γ-rays with average rise times of 65 µs are observed, which decreases to 20 µs when a higher electrical field of 500 V cm^-1 is applied. However, the baseline becomes noisy quickly, which prevents collection of clean pulses for spectra construction. Further, by systematically measuring the temperature dependence and current–voltage characteristics, such instability is attributed to the local ion migration under electrical field creating a fluctuating dark noise, which presents a major challenge in perovskite γ-ray detector technologies. It is demonstrated that cycling the bias between positive and negative polarity can stabilize the detector, allowing for longer periods of pulse accumulation for generating energy resolved spectra with resolutions of ≈35% at 59.6 keV and ≈25% at 662 keV at room temperature. The study indicates that the main limiting factors of perovskite-based γ-ray detectors are slow rise times and bias instability. Finally, these challenges must be properly addressed to achieve reproducible, high-resolution γ-ray detection.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States). Center of Integrated Nanotechnology (CINT)
• Sponsoring Organization: USDOE Laboratory Directed Research and Development (LDRD) Program
• Grant/Contract Number: 89233218CNA000001; 20180026DR
• OSTI ID: 1630883
• Alternate ID(s): OSTI ID: 1607595
• Report Number(s): LA-UR-20-20127
• Journal Information: Advanced Optical Materials, Vol. 8, Issue 10; ISSN 2195-1071
• Publisher: WileyCopyright Statement
• Country of Publication: United States
• Language: English