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Optical probing of correlation driven liquid-to-insulator transition in 2D electron gas

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 نشر من قبل Vttorio Bellani Dr.
 تاريخ النشر 2010
  مجال البحث فيزياء
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We study the quantum Hall liquid and the metal-insulator transition in a high mobility two dimensional electron gas, by means of photoluminescence and magneto-transport. In the integer and fractional regime at nu > 1/3, analyzing the emission energy dispersion we probe the magneto-Coulomb screening and the hidden symmetry of the electron liquid. In the fractional regime above above nu =1/3 the system undergoes the metal-to-insulator transition, and in the insulating phase the dispersion becomes linear with evidence of an increased renormalized mass.

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