Single Particle Spectroscopy of CdTe QDs

Third-order nonlinear optical properties of CdTe QDs were examined by Z-scan and FWM experiments in the nonresonant wavelength region. We found that the two-photon absorption cross section, a, is as high as 10 GM, although this value decreases with decreasing size. In addition, the nonlinear response is comparable to the pulse width of a fs laser and the figures of merit (FOM = Re Xqd/ Xqd) 

The authors gratefully thank Dr K. Kamada, Dr V. Biju, and Dr M. Ishikawa. This work was partly supported by Grant-in-Aid for Scientific Research on Priority Areas of Molecular Nano Dynamics, from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan. 

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