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Abstract In high fluence applications of lead halide perovskites for light-emitting diodes and lasers, multi-polaron interactions and associated Auger recombination limit the device performance. However, the relationship of the ultrafast and strongly lattice coupled carrier dynamics to nanoscale heterogeneities has remained elusive. Here, in ultrafast visible-pump infrared-probe nano-imaging of the photoinduced carrier dynamics in triple cation perovskite films, a ~20 % variation in sub-ns relaxation dynamics with spatial disorder on tens to hundreds of nanometer is resolved. We attribute the non-uniform relaxation dynamics to the heterogeneous evolution of polaron delocalization and increasing scattering time. The initial high-density excitation results in faster relaxation due to strong many-body interactions, followed by extended carrier lifetimes at lower densities. These results point towards the missing link between the optoelectronic heterogeneity and associated carrier dynamics to guide synthesis and device engineering for improved perovskites device performance. 

The main goal of the field of neuromorphic computing is to build machines that emulate aspects of the brain in its ability to perform complex tasks in parallel and with great energy efficiency. Thanks to new computing architectures, these machines could revolutionize high-performance computing and find applications to perform local, low-energy computing for sensors and robots. The use of organic and soft materials in neuromorphic computing is appealing in many respects, for instance, because it allows better integration with living matter to seamlessly meld sensing with signal processing, and ultimately, stimulation in a closed-feedback loop. Indeed, not only can the mechanical properties of organic materials match those of tissue, but also, the working mechanisms of these devices involving ions, in addition to electrons, are compatible with human physiology. Another advantage of organic materials is the potential to introduce novel fabrication techniques relying on additive manufacturing amenable to one-of-a-kind form factors. This field is still nascent, therefore many concepts are still being proposed, without a clear winner. Furthermore, the field of application of organic neuromorphics, where bioinspiration and biointegration are extremely appealing, calls for a co-design approach from materials to systems.