Measurements of Composite Fermion Conductivity Dependence on Carrier Density

الأصل · EN

We present the first experimental study of the carrier density dependence of the composite fermion conductivity σCFxx at Landau level filling factors ν= 1/2 and ν= 3/2 in high-quality front-gated GaAs/Al₀.₃₃Ga₀.₆₇As heterostructures. Extracting α from the power law ln(σCFxx) ∝ ln(nₑ)α shows that α≈ 1. The measured α ≈ 1 is placed between the predicted value 3/4 in the strong random magnetic field regime, and 3/2 in the weak random magnetic field regime. Comparisons between our results and theory are discussed.