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Many-body two-quantum coherences in semiconductor nanostructures

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 Added by Steven Cundiff
 Publication date 2009
  fields Physics
and research's language is English




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We present experimental coherent two-dimensional Fourier transform spectra of the exciton resonances in semiconductor quantum wells for a pulse sequence that isolates two-quantum coherences. By measuring the real part of the spectra, we can determine that the spectra are dominated by two quantum coherences due to many-body interactions, not bound biexcitons. Simulations performed using dynamics controlled truncation agree well with the experiments.



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