Metal nanoparticles with plasmon resonances for optoelectronics and biomedicine

In the laboratory “Surface Photophysics” we investigate composite materials with nanoparticles of noble metals. An attractive feature of noble metal nanoparticles is that all of their conduction electrons oscillate collectively in response to a external electromagnetic field. Due to this, their response to the external stimulus is larger as compared to other resonance systems. Simultaneously, a region of greatly enhanced electric field strength is formed in the close proximity of the nanoparticles. By placing in this region different resonance systems that possess useful but weak response to the electromagnetic field one can attain considerable enhancement of absorption and luminescence, as well as the rates of other processes. The obtained by us novel composites comprising epitaxial quantum dots in monocrystalline gallium arsenide are of special interest due to the feasibility of their use in optoelectronic devices. We also study composites with organic dyes, especially those that form J-aggregates. The application of nanoparticles in the investigation of processes in living cells is also underway.