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Critical Behavior of a Strongly Interacting 2D Electron System

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 نشر من قبل Myriam P. Sarachik
 تاريخ النشر 2011
  مجال البحث فيزياء
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With decreasing density $n_s$ the thermopower $S$ of a low-disorder 2D electron system in silicon is found to exhibit a sharp increase by more than an order of magnitude, tending to a divergence at a finite, disorder-independent density $n_t$ consistent with the critical form $(-T/S) propto (n_s-n_t)^x$ with $x=1.0pm 0.1$ ($T$ is the temperature). Our results provide clear evidence for an interaction-induced transition to a new phase at low density in a strongly-interacting 2D electron system.

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