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Ultrafast Optical Response of a High-Reflectivity GaAs/AlAs Bragg Mirror

Sara R. Hastings·Michiel J. A. de Dood·Hyochul Kim·William Marshall·Hagai S. Eisenberg·Dirk Bouwmeester
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Abstract

The ultrafast response of a high-reflectivity GaAs/AlAs Bragg mirror to optical pumping is investigated for all-optical switching applications. Both Kerr and free carrier nonlinearities are induced with 100 fs, 780 nm pulses with a fluence of 0.64 kJ/m^2 and 0.8 kJ/m^2. The absolute transmission of the mirror at 931 nm increases by a factor of 27 from 0.0024% to 0.065% on a picosecond timescale. These results demonstrate the potential for a high-reflectivity ultrafast switchable mirror for quantum optics and optical communication applications. A design is proposed for a structure to be pumped below the bandgaps of the semiconductor mirror materials. Theoretical calculations on this structure show switching ratios up to 2200 corresponding to switching from 0.017% to 37.4% transmission.

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Sara R. Hastings, Michiel J. A. de Dood, Hyochul Kim, William Marshall, Hagai S. Eisenberg, Dirk Bouwmeester. 2004-11-11. Ultrafast Optical Response of a High-Reflectivity GaAs/AlAs Bragg Mirror. https://doi.org/10.1063/1.1854200

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