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Transistor operation and mobility enhancement in top-gated LaAlO_3 / SrTiO_3 heterostructures

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 نشر من قبل Chris Bell
 تاريخ النشر 2013
  مجال البحث فيزياء
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We report the operation of LaAlO_3 / SrTiO_3 depletion mode top-gated junction field-effect transistors using a range of LaAlO_3 thicknesses as the top gate insulator. Gated Hall bars show near ideal transistor characteristics at room temperature with on-off ratios greater than 1000. Lower temperature measurements demonstrate a systematic increase in the Hall mobility as the sheet carrier density in the channel is depleted via the top gate, providing a route to higher mobility, lower density electron gases in this system.



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