So-called quantum dots are a unusual class of materials with many applications. Quantum dots are realized by petite semiconductor crystals with dimensions within the nanometre range. The optical and electrical properties could likely well perchance moreover moreover be managed by the scale of these crystals. As QLEDs, they’re already accessible on the market within the most contemporary generations of TV flat monitors, the place they manufacture obvious in particular intellectual and high-resolution color reproduction. However, quantum dots are no longer only historical as “dyes,” they’re also historical in report voltaic cells or as semiconductor devices, correct up to computational building blocks, the qubits, of a quantum computer.
Now, a team led by Dr. Annika Bande at HZB has extended the view of the interaction between several quantum dots with an atomistic stare in a theoretical newsletter.
Annika Bande heads the “Understanding of Electron Dynamics and Spectroscopy” neighborhood at HZB and is in particular attracted to the origins of quantum physical phenomena. Despite the indisputable reality that quantum dots are extremely petite nanocrystals, they embody hundreds of atoms with, in turn, multiples of electrons. Even with supercomputers, the electronic building of this form of semiconductor crystal could likely well perchance moreover hardly ever ever be calculated, emphasises the theoretical chemist, who recently carried out her habilitation at Freie Universität. “But we’re establishing programs that portray the topic approximately,” Bande explains. “In this case, we worked with scaled-down quantum dot variations of only just a few hundred atoms, which nonetheless feature the attribute properties of proper nanocrystals.”
With this vogue, after a year and a half of of building and in collaboration with Prof. Jean Christophe Tremblay from the CNRS-Université de Lorraine in Metz, we succeeded in simulating the interaction of two quantum dots, every made of hundreds of atoms, which alternate vitality with every other. Particularly, now we relish investigated how these two quantum dots can absorb, alternate and completely retailer the vitality managed by mild. A dawn pulse is historical for excitation, whereas the second mild pulse induces the storage.
In entire, we investigated three different pairs of quantum dots to deem the effect of size and geometry. We calculated the electronic building with highest precision and simulated the electronic movement in proper time at femtosecond resolution (10-15 s).
The outcomes are also very advisable for experimental study and building in so a lot of fields of application, as an instance for the development of qubits or to support photocatalysis, to construct green hydrogen gasoline by sunlight. “We are continuously engaged on extending our fashions in direction of a lot extra life like descriptions of quantum dots,” says Bande, “e.g. to deem the affect of temperature and ambiance.”
Supplies offered by Helmholtz-Zentrum Berlin für Materialien und Energie. Show veil: Stammer material could likely well perchance moreover be edited for kind and length.