This article is cited in 19 papers

Nonlinear optical phenomena

Self-diffraction of ultrashort laser pulses under resonant excitation of excitons in a colloidal solution of CdSe/ZnS quantum dots

V. S. Dneprovskii, M. V. Kozlova, A. M. Smirnov

Lomonosov Moscow State University, Faculty of Physics

Abstract: We report self-diffraction processes of two types under resonant excitation of the fundamental electron – hole (exciton) transition in a strongly absorbing colloidal solution of CdSe/ZnS quantum dots (QDs) by high-power picosecond laser pulses. In the first case the absorption saturation (bleaching) at the exciton transition frequency and the Stark shift of exciton absorption line lead to the formation of a transparency channel and self-diffraction of the laser beam from the thus induced round diaphragm. In the second case, self-diffraction of two laser beams, intersecting in a cell with a colloidal QD solution, occurs on the diffraction grating induced by these beams. The physical processes responsible for the nonlinear optical properties of CdSe/ZnS QDs and the found selfaction effects are analysed.

Keywords: semiconductor quantum dots, self-diffraction, exciton, induced diffraction grating, absorption saturation, Stark effect.

PACS: 73.21.La, 71.35.-y, 42.65.Re, 42.25.Fx

Received: 13.06.2013

 English version: Quantum Electronics, 2013, 43:10, 927–930

Bibliographic databases:

• 
• 
• 
•