Intense Electrical Pulsing of Perovskite Light Emitting Diodes under Cryogenic Conditions

Abstract

As the threshold for stimulated emission is significantly reduced at cryogenic temperatures, cooling of perovskite light emitting diodes (PeLEDs) is considered an essential strategy for reaching injection lasing in perovskite diodes. In this work, we demonstrate the intense electrical pulsing of a PeLED stack up to a few kA cm(-2) at cryogenic conditions. A high external quantum efficiency (EQE) of 2.9% at 1 kA cm(-2) and a radiance >1.95 x 10(5) W Sr-1 m(-2) are achieved when exciting the device with 250 ns electrical pulses at 77 K, showing three times enhancement in comparison with room temperature operation. Furthermore, we provide a comprehensive understanding on how the ion distribution can affect the PeLED characteristics and show that ion motions can be manipulated at cryogenic conditions. This opens new routes for novel material and device designs for further improving PeLED performance.