Cookies on this website
We use cookies to ensure that we give you the best experience on our website. If you click 'Continue' we will assume that you are happy to receive all cookies and you will not see this message again. Click 'Find out more' for information on how to change your cookie settings.

We present transient four-wave mixing experiments on individual excitonic transitions in self-assembled CdTe/ZnTe quantum dots. Using a two-dimensional femtosecond spectroscopy and heterodyne detection of the nonlinear signal we study the dephasing and mutual coherent coupling of single quantum dot states. For the homogeneous linewidth of the zero-phonon line (ZPL) values of 0.06-0.1 meV (T2 =13-20 ps) are measured, and a ZPL weight in the total line shape of Z=0.9 at T=7 K is estimated. We observe two linearly polarized fine-structure split exciton transitions with transition dipole moment ratios of 1.0-1.1 deduced from the four-wave mixing (FWM) amplitude, and splitting energies of 0.2-0.35 meV deduced from the FWM spectral response or quantum beat period. Coherent coupling between excitonic states is identified by off-diagonal signals in the two-dimensional spectrally-resolved FWM. The presence of an inhomogeneous broadening caused by spectral diffusion in the time ensemble is evidenced by the formation of a photon echo in the time-resolved FWM from a single transition. © 2006 The American Physical Society.

Original publication

DOI

10.1103/PhysRevB.73.235354

Type

Journal article

Journal

Physical Review B - Condensed Matter and Materials Physics

Publication Date

07/07/2006

Volume

73