Fig. 2: Charge transport and X-ray detection performance of MAPbI3 SC XPV detectors.
From: Stable perovskite single-crystal X-ray imaging detectors with single-photon sensitivity
a, I–V curves in the dark and under X-ray and light illumination, used to estimate the build-in potential of ~1.1 V. b,c, ToF traces for holes (b) and electrons (c) under blue laser pulses for various bias voltages, used to determine the charge carrier mobility. d, X-ray DE dependence on thickness for different X-ray photon energies (shown in different colours), calculated based on models (lines) with upper (solid) and lower (dashed) limits of µτ evaluation. The open circles represent the experimental DE data. The data points represent the mean values and the error bars are r.m.s. deviations. They are estimated for 9,600 on/off cycles with a lock-in amplifier (for 960 Hz modulation frequency of X-rays and 10 s integration time), accounting for the error in dose rate measurements and accuracy of detector area estimation. e, Squared-noise-current spectral density dependence on the dose rate together with NT2, expressed in photon equivalents, depending on the mean photon number over an integration time of 500 µs (the black circles are experimental data and the black line is the fit with equation (3)). f, NED (black line) and DQE (green lines) versus photon energy, calculated from the experimental DE and NED; DQE is shown for a single photon (solid line) and 100 photons (dashed line); the energy ranges where only the charge-integration regime is possible and the photon-counting regime becomes allowed are highlighted in yellow and blue, respectively. The optimal energy range is shaded in red.
