Séminaire DQMP - SEMICONDUCTOR NANOCRYSTALS AND QUANTUM DOTS

12.03.2024 13:00 – 14:00

In 1981, Aleksei Ekimov and coauthors (Vavilov State Optical Institute, Leningrad) reported experimental observation of the quantum-size effect in semiconductor nanocrystals embedded into glass matrix. In 1983 Louis Brus and coauthors (Bell Laboratories, Murray Hill) independently reported quantum size effect in nanocrystals dispersed in aqueous solution. These optical studies lay foundation to a new field - the physics and technology of zero-dimensional structures. Modern technology of chemical synthesis established by Moungi Bawendi (Bell Laboratories and, later, MIT, Cambridge) allows to obtain monodisperse nanocrystals of various shape and size from such semiconductors as CdSe, CdTe, InP, PbS and many others. Optical properties of these zero-dimensional nanocrystals, later coined quantum dotes (QD), are determined by the quantum size effect. Nowadays QDs are widely used in applications: optoelectronics (white light sources, LEDs, displays and TVs), photovoltaics (solar cells), medicine and biology (sensors and labels). In 2023, A. Ekimov, L. Brus and M. Bawendi were awarded the Nobel Prize in Chemistry for the "discovery and synthesis of quantum dots"
In my talk I will present a review on the history of this discovery and outline the directions of current research and applications of colloidal semiconductor nanocrystals. Aside the quantum-size effect, the influence of the nanocrystal surface is important for understanding electronic and optical properties of colloidal QDs. Similarities and differences between colloidal and epitaxial QDs will be also discussed.


Organisateur : Louk Rademeker

Lieu

Bâtiment: Ecole de Physique

Auditoire Stückelberg

entrée libre