Slow Auger Recombination of Charged Excitons in Nonblinking Perovskite Nanocrystals without Spectral Diffusion

TL;DR

This paper demonstrates that nonblinking photoluminescence and significantly slowed Auger recombination occur in CsPbI3 perovskite nanocrystals, with no spectral diffusion at cryogenic temperatures, indicating improved stability and optical properties.

Contribution

It reveals that CsPbI3 nanocrystals exhibit nonblinking PL and suppressed Auger recombination without spectral diffusion, advancing understanding of their optical stability.

Findings

Nonblinking PL observed in CsPbI3 NCs

Auger recombination of charged excitons is greatly slowed

Spectral diffusion is absent at cryogenic temperatures

Abstract

Over the last two decades, intensive research efforts have been devoted to the suppressions of photoluminescence (PL) blinking and Auger recombination in metal-chalcogenide nanocrystals (NCs), with significant progresses being made only very recently in several specific heterostructures. Here we show that nonblinking PL is readily available in the newly-synthesized perovskite CsPbI3 (cesium lead iodide) NCs, and their Auger recombination of charged excitons is greatly slowed down, as signified by a PL lifetime about twice shorter than that of neutral excitons. Moreover, spectral diffusion is completely absent in single CsPbI3 NCs at the cryogenic temperature, leading to a resolution-limited PL linewidth of ~200 {\mu}eV.