Publications by authors named "K H Ploog"

The temperature-dependent polarized photoluminescence spectra of nonpolar ZnO samples were investigated by 263 nm laser. The degree of polarization (DOP) of m-plane quantum wells changes from 76% at 10 K to 40% at 300 K, which is much higher than that of epilayer. The strong anisotropy was presumably attributed to the enhanced confinement effect of a one-dimension confinement structure formed by the intersection of quantum well and basal stacking fault.

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Zn1-xMgxO films with x = 0.04-0.50 grown on MgO (100) substrates by molecular beam epitaxy retain the rocksalt (rs) crystal structure and grow epitaxially for x ≥ 0.

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We perform Young's double-slit experiment to study the spatial coherence properties of a two-dimensional dynamic condensate of semiconductor microcavity polaritons. The coherence length of the system is measured as a function of the pump rate, which confirms a spontaneous buildup of macroscopic coherence in the condensed phase. An independent measurement reveals that the position and momentum uncertainty product of the condensate is close to the Heisenberg limit.

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The Al compositional distribution of AlGaN is investigated by cathodoluminescence (CL). Monochromatic CL images and CL spectra reveal a lateral Al compositional inhomogeneity, which corresponds to surface hexagonal patterns. Cross-sectional CL images show a relatively uniform Al compositional distribution in the growth direction, indicating columnar growth mode of AlGaN films.

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