All-optical switching due to state-filling in quantum dots

R. Prasanth; J. E. M. Haverkort; A. Deepthy; E. W. Bogaart; J. J. G. M. van der Tol; E. A. Patent; G. Zhao; Q. Gong; P. J. van Veldhoven; R. Noetzel; J. H. Wolter

doi:10.1063/1.1751617

arXiv · cond-mat/0410440

All-optical switching due to state-filling in quantum dots

R. Prasanth·J. E. M. Haverkort·A. Deepthy·E. W. Bogaart·J. J. G. M. van der Tol·E. A. Patent·G. Zhao·Q. Gong·P. J. van Veldhoven·R. Noetzel·J. H. Wolter

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Abstract

We report all-optical switching due to state-filling in quantum dots (QDs) within a Mach-Zehnder Interferometric (MZI) switch. The MZI was fabricated using InGaAsP/InP waveguides containing a single layer of InAs/InP QDs. A 1530-1570 nm probe beam is switched by optical excitation of one MZI-arm from the top. By exciting below the InGaAsP bandgap, we prove that the refractive index nonlinearity is only due to the QDs. The switching efficiency is 2 rad/(microW absorbed power). Probe wavelength insensitivity was obtained using a broad distribution of QDs.

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R. Prasanth, J. E. M. Haverkort, A. Deepthy, E. W. Bogaart, J. J. G. M. van der Tol, E. A. Patent, G. Zhao, Q. Gong, P. J. van Veldhoven, R. Noetzel, J. H. Wolter. 2004-10-18. All-optical switching due to state-filling in quantum dots. https://doi.org/10.1063/1.1751617

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