Three-pulse photon echo induced by the optical transition of excitons in core–shell CdSe/ZnS nanocrystal quantum dots

The femtosecond three-pulse photon echo phenomena induced by the optical transition of 1s(e)1s(h) exciton in a core-shell CdSe/ZnS nanocrystal quantum dot (NQD) are theoretically investigated basing on the optical Bloch equations. The parameter dependence of the photon echo signals is discussed. The numerical calculation results reveal that three-pulse photon echo signals are sensitive to the variation of the size and structure of NQD. The corresponding mechanism has been discussed in terms of quantum size confined effect theory. (C) 2011 Elsevier B.V. All rights reserved.