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arXiv · 2008.11953

Optical second and third harmonic generation on excitons in ZnSe/BeTe quantum wells

Johannes Mund·Andreas Farenbruch·Dmitri R. Yakovlev·Andrei A. Maksimov·Andreas Waag·Manfred Bayer
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Abstract

Optical harmonic generation on excitons is found in ZnSe/BeTe quantum wells with type-II band alignment. Two experimental approaches with spectrally-broad femtosecond laser pulses and spectrally-narrow picosecond pulses are used for spectroscopic studies by means of second and third harmonic generation (SHG and THG). The SHG signal is symmetry-forbidden for light propagation along the structure's growth axis, which is the [001] crystal axis, but can be induced by an external magnetic field. The THG signal is detected at zero magnetic field and its intensity is field independent. A group theory analysis of SHG and THG rotational anisotropy diagrams allows us to identify the involved excitation mechanisms.

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Johannes Mund, Andreas Farenbruch, Dmitri R. Yakovlev, Andrei A. Maksimov, Andreas Waag, Manfred Bayer. 2020-08-27. Optical second and third harmonic generation on excitons in ZnSe/BeTe quantum wells. https://doi.org/10.1103/physrevb.102.125433

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