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تسجيل مستخدم جديدLogarithmic temperature dependence of conductivity at half-integer filling factors: Evidence for interaction between composite fermions
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We have studied the temperature dependence of diagonal conductivity in high-mobility two-dimensional samples at filling factors $ u=1/2$ and 3/2 at low temperatures. We observe a logarithmic dependence on temperature, from our lowest temperature of 13 mK up to 400 mK. We attribute the logarithmic correction to the effects of interaction between composite fermions, analogous to the Altshuler-Aronov type correction for electrons at zero magnetic field. The paper is accepted for publication in Physical Review B, Rapid Communications.
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Composite fermions in fractional quantum Hall (FQH) systems are believed to form a Fermi sea of weakly interacting particles at half filling $ u=1/2$. Recently, it was proposed (D. T. Son, Phys. Rev. X 5, 031027 (2015)) that these composite fermions
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