Optical and electrical properties of all-inorganic Cs2AgBiBr6 double perovskite single crystals

In this work, we explored the possibility of using Cs2AgBiBr6, a double perovskite crystal, for radiation detection. Cs2AgBiBr6 crystals were grown using the solution growth technique. The resistivity of the as-grown Cs2AgBiBr6 crystal is larger than 1010 Ω cm, which is high enough to ensure low leakage current for fabrication of semiconductor radiation detectors. Using the temperature-dependent resistivity measurements, we estimated that the Fermi level is at 0.788 eV above the valence band and the material is a p-type semiconductor. From the low-temperature cathodoluminescence measurements, two near band gap energies at 1.917 eV and 2.054 eV were revealed.