Figure 2. Characterizations of the perovskite diodes when working as the light emitter.
a, External quantum efficiency (EQE) and radiance versus current density curves of the optimized perovskite LEDs. The inset is the photograph of the LED driven by a 3.0 V bias. b, Transient EL intensity and current characterization of the perovskite LEDs. c, Frequency response curves of the perovskite LED under different drive pulse voltages. d, Frequency response of perovskite LEDs with different device areas.