Ultrafast Dynamics of Quantum Dots

Semiconductor nanocrystals (Quantum Dots) have excellent potential as the next generation of smart materials for a myriad of applications including fluorescence imaging of biological samples, solid-state laser systems, and photovoltaics for optical switching and power generation. Understanding the fundamental processes governing the optical properties of these materials is essential for their continued development. Using advanced spectroscopic techniques we aim to determine the effect of multi-exciton interactions and wavefunction delocalisation to enhance QDs quantum yield and efficiency as a laser gain medium.  Shown is 3-Pulse Photon Echo Peakshift data collected for a series of QD samples.  Of particular note are the vibrational modes and the varied peakshift asymptote (y-axis) of the samples.

Peakshift

Relevant papers:

  • L.J McKimmie, C.N. Lincoln, J. Jasieniak and T.A. Smith, “3-Pulse Photon Echo Peak Shift Measurements of Capped CdSe Quantum Dots”, J. Phys. Chem. C. 114, 82-88, (2010)