TY - JOUR

T1 - How strong is localization in the integer quantum Hall effect

T2 - Relevant quantum corrections to conductivity in non-zero magnetic field

AU - Greshnov, A. A.

AU - Kolesnikova, E. N.

AU - Utesov, O. I.

AU - Zegrya, G. G.

PY - 2010/2/1

Y1 - 2010/2/1

N2 - The divergent at ω = 0 quantum correction to conductivity δ σ2 (ω) of the leading order in (kF l)- 1 has been calculated neglecting Cooperon-type contributions suppressed by moderate or strong magnetic field. In the so-called diffusion approximation this quantity is equal to zero up to the second order in (kF l)- 1. More subtle treatment of the problem shows that δ σ2 (ω) is non-zero due to ballistic contributions neglected previously. Knowledge of δ σ2 (ω) allows to estimate value of the so-called unitary localization length as ξu ≈ l exp (1.6 g2) where Drude conductivity is given by σ0 = ge2 / h. This estimation underpins the statement of the linear growth of σxx peaks with Landau level number n in the integer quantum Hall effect regime [1] (Greshnov and Zegrya, 2008; Greshnov et al., 2008) at least for n ≤ 2 and calls Pruisken-Khmelnitskii hypothesis of universality [2] (Levine et al., 1983; Khmelnitskii, 1983) in question.

AB - The divergent at ω = 0 quantum correction to conductivity δ σ2 (ω) of the leading order in (kF l)- 1 has been calculated neglecting Cooperon-type contributions suppressed by moderate or strong magnetic field. In the so-called diffusion approximation this quantity is equal to zero up to the second order in (kF l)- 1. More subtle treatment of the problem shows that δ σ2 (ω) is non-zero due to ballistic contributions neglected previously. Knowledge of δ σ2 (ω) allows to estimate value of the so-called unitary localization length as ξu ≈ l exp (1.6 g2) where Drude conductivity is given by σ0 = ge2 / h. This estimation underpins the statement of the linear growth of σxx peaks with Landau level number n in the integer quantum Hall effect regime [1] (Greshnov and Zegrya, 2008; Greshnov et al., 2008) at least for n ≤ 2 and calls Pruisken-Khmelnitskii hypothesis of universality [2] (Levine et al., 1983; Khmelnitskii, 1983) in question.

KW - Crossed diffusons

KW - Disorder

KW - Integer quantum Hall effect

KW - Magnetic field

KW - Quantum corrections to conductivity

KW - Weak localization

UR - http://www.scopus.com/inward/record.url?scp=76949091594&partnerID=8YFLogxK

U2 - 10.1016/j.physe.2009.10.025

DO - 10.1016/j.physe.2009.10.025

M3 - Article

AN - SCOPUS:76949091594

VL - 42

SP - 1062

EP - 1065

JO - Physica E: Low-Dimensional Systems and Nanostructures

JF - Physica E: Low-Dimensional Systems and Nanostructures

SN - 1386-9477

IS - 4

ER -