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The absorption spectrum around nu=1: evidence for a small size Skyrmion

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 نشر من قبل Javier Groshaus Javier Groshaus
 تاريخ النشر 2004
  مجال البحث فيزياء
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We measure the absorption spectrum of a two-dimensional electron system (2DES) in a GaAs quantum well in the presence of a perpendicular magnetic field. We focus on the absorption spectrum into the lowest Landau Level around nu=1. We find that the spectrum consists of bound electron-hole complexes, trion and exciton like. We show that their oscillator strength is a powerful probe of the 2DES spatial correlations. We find that near nu=1 the 2DES ground state consists of Skyrmions of small size (a few magnetic lengths).

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