Researchers at Canada's McGill University have developed what they call a unique instrument hand-built by the team called multi-dimensional electronic spectrometer (MDES) that helped them discover perovskite's liquid-solid duality by the virtue of it being able to measure the behaviour of electrons over short periods of time, as short as 10 femtoseconds.
The cesium lead iodide perovskite nanocrystals (CsPBI3) were observed to behave like liquid in response to light. The two-dimensional spectroscopy revealed liquid-like line shape dynamics in CsPBI3 perovskite nanocrystals during the course of the research.
These revealed diffusive dynamics qualitatively inconsistent with the coherent dynamics in covalent solids as CdSe quantum dots.
"In contrast, these dynamics are consistent with liquid-like structural dynamics on the 100-femtosecond timescale. These dynamics are assigned to the optical signature of polaron formation, the conceptual solid-state analogue of solvation," as per the research. "Polaron formation arises from the dynamical coupling of atomic fluctuations to electronic states. Measuring the properties of these fluctuations is therefore essential in light of potential optoelectronic applications.
Senior author and Chemistry Professor at McGill, Patanjali Kambhampati explained that instead of searching for perfection in defect-free silicon microelectronics, they have figured out a defective thing that's defect-tolerant.
The study has found its way int the journal Nature Communications and is available for free viewing on its website.