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Diffusive Propagation of Exciton-Polaritons through Thin Crystal Slabs.

ABSTRACT: If light beam propagates through matter containing point impurity centers, the amount of energy absorbed by the media is expected to be either independent of the impurity concentration N or proportional to N, corresponding to the intrinsic absorption or impurity absorption, respectively. Comparative studies of the resonant transmission of light in the vicinity of exciton resonances measured for 15 few-micron GaAs crystal slabs with different values of N, reveal a surprising tendency. While N spans almost five decimal orders of magnitude, the normalized spectrally-integrated absorption of light scales with the impurity concentration as N(1/6). We show analytically that this dependence is a signature of the diffusive mechanism of propagation of exciton-polaritons in a semiconductor.

SUBMITTER: Zaitsev DA

PROVIDER: S-EPMC4473602 | biostudies-other | 2015

REPOSITORIES: biostudies-other

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