Prof. Uri Banin from the Hebrew University of Jerusalem: "Colloidal Semiconductor Quantum Dots: From Artificial Atoms to Designer Molecules"

Colloidal semiconductor quantum dots (QDs), often regarded as artificial atoms, have reached an exceptional level of synthetic control and fundamental understanding—particularly regarding their size, composition, and surface-dependent properties.

Their tunable characteristics, scalable bottom-up synthesis, and compatibility with solution-based processing have enabled widespread applications in displays, lasers, light-emitting diodes, single-photon sources, photodetectors, and beyond.

For the next step towards enhancing their functionalities, we take inspiration from molecular chemistry and present a strategy for the controlled linking and fusion of two core/shell QDs, creating artificial molecules with two coupled emissive centers.

These coupled colloidal quantum dot molecules (CQDMs) exhibit electronic level hybridization and optoelectronic behaviors that are fundamentally distinct from their individual QD constituents. Notably, CQDMs enable a novel electric-field-induced instantaneous color-switching effect—allowing for color tuning without loss of intensity—a feature unattainable with single QDs. These dual-emission quantum dot molecules can be engineered to emit distinct colors, offering new opportunities for electric field sensing and the development of color-switchable devices, such as innovative pixel architectures for next-generation displays or tunable photon sources.