TY - JOUR

T1 - Experimental study of σxx(T) for quasiparticle charge determination in the fractional quantum Hall effect

AU - Katayama, Y.

AU - Tsui, D. C.

AU - Shayegan, M.

PY - 1994

Y1 - 1994

N2 - The temperature dependence of the diagonal conductivity, σxx(T), at integer and fractional quantum Hall effect (FQHE) minima was measured in a sample at various densities. We find σxxc, the 1/T→0 extrapolated value of σxx(T) from Arrhenius plots, is different for different densities. While a reasonable (1/q)2 scaling of σxxc at the filling factors ν=p/q is observed at lower densities, the scaling is not seen in the highest density data. We explain this loss of scaling by a breakdown of the assumption for a simple activated formula caused by a crossover between the extended state width, Γ, and T for the measurement. For kT>Γ, the scaling of the 1/T intercept is recovered by plotting σxx(T)×T vs 1/T and fitting to σxx(T)=(σxx*c/T)exp(-ΔE/kT). We attribute the (1/q)2 scaling in σxxc and σxx*c observed at each density to a (1/q)2 scaling in the T=0 conductivity. This supports the assertion of Clark et al. that the charge e* of the quasiparticle excitation from the FQHE ground state at ν=p/q can be determined from σxx(T) and the charge is e*=e/q.

AB - The temperature dependence of the diagonal conductivity, σxx(T), at integer and fractional quantum Hall effect (FQHE) minima was measured in a sample at various densities. We find σxxc, the 1/T→0 extrapolated value of σxx(T) from Arrhenius plots, is different for different densities. While a reasonable (1/q)2 scaling of σxxc at the filling factors ν=p/q is observed at lower densities, the scaling is not seen in the highest density data. We explain this loss of scaling by a breakdown of the assumption for a simple activated formula caused by a crossover between the extended state width, Γ, and T for the measurement. For kT>Γ, the scaling of the 1/T intercept is recovered by plotting σxx(T)×T vs 1/T and fitting to σxx(T)=(σxx*c/T)exp(-ΔE/kT). We attribute the (1/q)2 scaling in σxxc and σxx*c observed at each density to a (1/q)2 scaling in the T=0 conductivity. This supports the assertion of Clark et al. that the charge e* of the quasiparticle excitation from the FQHE ground state at ν=p/q can be determined from σxx(T) and the charge is e*=e/q.

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U2 - 10.1103/PhysRevB.49.7400

DO - 10.1103/PhysRevB.49.7400

M3 - Article

AN - SCOPUS:0000741779

SN - 0163-1829

VL - 49

SP - 7400

EP - 7407

JO - Physical Review B

JF - Physical Review B

IS - 11

ER -