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arXiv · 1210.8096

Fifth-order nonlinear optical response of excitonic states in an InAs quantum dot ensemble measured with 2D spectroscopy

G. Moody·R. Singh·H. Li·I. A. Akimov·M. Bayer·D. Reuter·A. D. Wieck·S. T. Cundiff
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Abstract

Exciton, trion and biexciton dephasing rates are measured within the inhomogeneous distribution of an InAs quantum dot (QD) ensemble using two-dimensional Fourier-transform spectroscopy. The dephasing rate of each excitonic state is similar for all QDs in the ensemble and the rates are independent of excitation density. An additional spectral feature -- too weak to be observed in the time-integrated four-wave mixing signal -- appears at high excitation density and is attributed to the $χ^{\textrm{(5)}}$ biexcitonic nonlinear response.

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G. Moody, R. Singh, H. Li, I. A. Akimov, M. Bayer, D. Reuter, A. D. Wieck, S. T. Cundiff. 2012-10-30. Fifth-order nonlinear optical response of excitonic states in an InAs quantum dot ensemble measured with 2D spectroscopy. https://doi.org/10.1103/physrevb.87.045313

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