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Coulomb drag at ν= 1/2: Composite fermion pairing fluctuations

Iddo Ussishkin·Ady Stern
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Abstract

We consider the Coulomb drag between two two-dimensional electron layers at filling factor ν= 1/2 each, using a strong coupling approach within the composite fermion picture. Due to an attractive interlayer interaction, composite fermions are expected to form a paired state below a critical temperature T_c. We find that above T_c pairing fluctuations make the longitudinal transresistivity ρ_D increase with decreasing temperature. The pairing mechanism we study is very sensitive to density variations in the two layers, and to an applied current. We discuss possible relation to an experiment by Lilly et al. [Phys. Rev. Lett. 80, 1714 (1998)].

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Iddo Ussishkin, Ady Stern. 1998-08-03. Coulomb drag at ν= 1/2: Composite fermion pairing fluctuations. https://doi.org/10.1103/physrevlett.81.3932

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