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Spin and the Coulomb Gap in the Half-Filled Lowest Landau Level

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 نشر من قبل James P. Eisenstein
 تاريخ النشر 2016
  مجال البحث فيزياء
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The Coulomb gap observed in tunneling between parallel two-dimensional electron systems, each at half filling of the lowest Landau level, is found to depend sensitively on the presence of an in-plane magnetic field. Especially at low electron density, the width of the Coulomb gap at first increases sharply with in-plane field, but then abruptly levels off. This behavior appears to coincide with the known transition from partial to complete spin polarization of the half-filled lowest Landau level. The tunneling gap therefore opens a new window onto the spin configuration of two-dimensional electron systems at high magnetic field.



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