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Two-dimensional electron gas in a modulation-doped SrTiO3/Sr(Ti,Zr)O3 heterostructure

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 نشر من قبل Susanne Stemmer
 تاريخ النشر 2013
  مجال البحث فيزياء
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A two-dimensional electron gas (2DEG) in SrTiO3 is created via modulation doping by interfacing undoped SrTiO3 with a wider-band-gap material, SrTi1-xZrxO3, that is doped n-type with La. All layers are grown using hybrid molecular beam epitaxy. Using magnetoresistance measurements, we show that electrons are transferred into the SrTiO3, and a 2DEG is formed. In particular, Shubnikov-de Haas oscillations are shown to depend only on the perpendicular magnetic field. Experimental Shubnikov-de Haas oscillations are compared with calculations that assume multiple occupied subbands.



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