MOSCOW, October 4The Nobel Committee of the Royal Swedish Academy of Sciences awarded the prize in chemistry for the discovery of quantum dots to three scientists — Alexei Ekimov, a native of the USSR, and Americans Louis Bruce and Munga Bavendi.
“Over the past couple of decades, quantum dots have become not only a popular object of research, but have also received practical application in light-emitting and photovoltaic devices, optical chemosensors and photonic nanostructures,” comments Associate Professor of the Department of Condensed Matter Physics at the Institute of Nanotechnologies in Electronics, Spintronics and Photonics, National Research Nuclear University MEPhI , Candidate of Chemical Sciences Alexandra Freidzon.
The existence of quantum objects, such as holes, wires, and points, follows from the solution of the Schrödinger equation when the boundary conditions change, the scientist notes. “When constrained in one direction, a quantum well is obtained, in two directions a quantum wire is obtained, and in three directions a quantum dot is obtained. The 2000 Nobel Prize in Physics was awarded to the Russian scientist Zhores Ivanovich Alferov for semiconductor heterostructures in which the effects of quantum wells can manifest themselves,” explains Freidzon.
However, according to a researcher from MEPhI, nanoobjects themselves are unstable, they need to be stabilized somehow. “Without this, the nanoparticles stick together,” she adds.
The solution was found in the early 1980s by Leningrad scientist Alexey Ekimov, who stabilized copper chloride particles in glass and showed that the color of the resulting glass was determined by the size nanoparticles.
«The other two laureates worked with nanoparticles floating freely in solution. To do this, their surface had to be stabilized. And since the optical properties of nanoparticles depend on their size, it is critically important to be able to control their size,» says Alexandra Freidzon .
Thus, the researcher concludes, the Nobel Prize was awarded for the production of an important and useful object — nanoparticles with size-dependent optical properties (quantum dots), a method for stabilizing their surface, and a method for obtaining particles of a given size.