Nobel Prize in Chemistry 2023 recognizes the work of scientists Mungi Bavendi, Louis Bruce, and Alexey Ekimov for the discovery and synthesis of quantum dots.
The laureates made particles so tiny that their behavior is governed by quantum phenomena, including radiation processes, atomic and nuclear physics, condensed matter physics, and chemical bonds. While ordinary particles’ properties are mostly set by electron count, quantum particles depend on size itself.
Thus, the smallest quantum dots emit blue light, medium-sized dots shine green, and the largest dots glow red or orange. Size is the key feature that alters thermal, magnetic, chemical, and electrical properties of these dots.
Ekimov and Bruce were the first to observe this effect in the 1980s.
What does stained glass have to do with it?
Historically, metals such as cadmium and copper were added to transparent glasses. When heated, these materials formed structures whose colors changed with size. Although ancient artisans did not know about quantum dots, Ekimov later realized that the size of the quantum structures inside glass controlled color. This insight came from work at the Ioffe Physico-Technical Institute, according to a director there. [Citation: Ioffe Institute archival testimony]
During firing, nanostructures formed on the glass surface and displayed surprising properties.
As research progressed, it became possible to form quantum dots in liquid environments. In the 1990s, metals immersed in colloidal solutions could be heat treated to create quantum dots. These dots could be isolated, studied independently, and even used in medicine. This opened a bridge between chemistry, physics, and biology, as explained by researchers at the time. [Citation: scientific interviews]
These dots can be magnetized and guided to target tissues, or solutions can be used to highlight tumor edges for medical imaging.
Current work includes experiments that apply quantum-dot liquids to tumor regions, helping surgeons visualize boundaries when illuminated by laser light. In vitro studies at MIPT aim to refine a fluid containing quantum dots for surgical use, per the laboratory leadership there. [Citation: MIPT communications]
“like a sandwich”
A second method, already adopted in semiconductor technology, relies on the self-organization of materials. An additional thin layer is added to a semiconductor surface. Tension between different parameters causes the sprayed material to cluster, and when topped with material underneath, quantum dots emerge as objects composed of multiple materials. This is the basis for semiconductor quantum dots.
It is described as a sandwich, with a three-layer plane and islands whose dimensions approach the electron mean free path. This approach underpins the development of semiconductor lasers, a technology foundational to modern telecommunications.
Quantum-dot lasers emerged in the USSR and remain under active development, including in Russia. They convert electrical signals into optical signals that travel through fiber. Quantum dots also serve as photon sources for optical quantum computers and can enable quantum-unhackable communications, as single-photon energy is required for these schemes. [Citation: expert interviews]
These technologies are pertinent to optical quantum computing, where photons carry information. Active development in this area is ongoing in Russia and beyond. [Citation: regional science reports]
native of the USSR
Ekimov pioneered the early study of quantum dots by demonstrating quantum effects in copper chloride nanoparticles and showing how particle size affects color. He studied at Leningrad State University and worked with leading figures at the Ioffe Institute, where optical spectroscopy and related effects were investigated. Later, he moved to the Ekimov State Optical Institute to explore glasses that change color with annealing temperature. Doping glasses with copper, chlorine, cadmium, sulfur, selenium, and other elements led to nano-sized clusters forming during annealing. [Citation: historical accounts]
In 1975, Ekimov received the USSR State Prize for work on spin orientation in semiconductors and earned the Doctor of Physical and Mathematical Sciences degree in 1989.
The line of research continued with the Vavilov Institute, which developed methods to produce nanometer-sized crystals in glassy matrices and linked crystal size to spectroscopic parameters. The broader field of semiconductor nanocrystals began to be called quantum dots, and Ekimov’s early work is considered foundational to this area. He later moved to the United States and joined a private company focusing on nanocrystal technology. [Citation: institutional histories]
Former colleagues recall ongoing collaboration and discussions about the properties of quantum dots, including methods to characterize them via Raman scattering. While hypotheses varied, the consensus centers on quantum-size effects as the primary driver of observed properties. [Citation: scientific discussions]
Family athlete and trophy collector
American chemist Mungi Bawendi woke in the night to learn of the award. He described a mix of sleepiness, shock, and praise for the honor, noting that the winners were announced ahead of the official release, yet he had not personally received a call. He emphasizes balance between work and family as essential to success. [Citation: interviews with The Tech]
Bawendi is a Harvard and University of Chicago alumnus and currently a professor of chemistry at MIT. He stresses that maintaining balance and rest is critical for sustained research and teaching, with his daughter and sports playing important roles in his life. He enjoys skiing, swimming, running, and other activities, and he prioritizes time with family alongside science. [Citation: professor profiles]
Louis Bruce of Columbia University is also highlighted for a long record of awards recognizing his work on semiconductor microcrystals in colloidal solutions, widely known as quantum dots. His career spans roles at Rice University and Columbia University, with a strong emphasis on the practical implications of quantum dots in communications and materials science. His achievements include multiple prestigious awards and leadership within the field. [Citation: award histories]
Bruce’s early career intertwined naval service and scientific study, ultimately guiding him toward a lifelong commitment to research in physical chemistry and nanoscience. His family background includes a diverse lineage, with influences from mathematics and practical problem solving that shaped his approach to science. [Citation: biographical summaries]
These narratives underscore how curiosity, persistence, and close collaboration across disciplines propelled quantum dot science from labs to real-world technologies. [Citation: biographical compendiums]