Ultrafast Symmetry Control in Photoexcited Quantum Dots.

ABSTRACT: Symmetry control is essential for realizing unconventional properties, such as ferroelectricity, nonlinear optical responses, and complex topological order, thus it holds promise for the design of emerging quantum and photonic systems. Nevertheless, fast and reversible control of symmetry in materials remains a challenge, especially for nanoscale systems. Here, reversible symmetry changes are unveiled in colloidal lead chalcogenide quantum dots on picosecond timescales. Using a combination of ultrafast electron diffraction and total X-ray scattering, in conjunction with atomic-scale structural modeling and first-principles calculations, it is revealed that symmetry-broken lead sulfide quantum dots restore to a centrosymmetric phase upon photoexcitation. The symmetry restoration is driven b

SUBMITTER: Guzelturk B 

PROVIDER: S-EPMC11775883 | biostudies-literature | 2025 Jan

REPOSITORIES: biostudies-literature