Low Temperature Physics: 43, 491 (2017); https://doi.org/10.1063/1.4983333
Fizika Nizkikh Temperatur: Volume 43, Number 4 (April 2017), p. 612-617    ( to contents , go back )

Insulator–quantum Hall transition in n-InGaAs/GaAs heterostructures

A.P. Savelyev1, S.V. Gudina1, Yu.G. Arapov1, V.N. Neverov1, S.M. Podgornykh1,2, and M.V. Yakunin1,2

1Федеральное государственное бюджетное учреждение науки Институт физики металлов им. М.Н. Михеева УРО РАН, ул. С. Ковалевской, 18, г. Екатеринбург, 620041, Россия
E-mail: saveliev@imp.uran.ru

2Уральский федеральный университет им. первого Президента России Б.Н. Ельцина ул. Мира, 19, г. Екатеринбург, 620002, Россия
pos Анотація:

Received December 19, 2016

Abstract

Longitudinal ρxx(B, T) and Hall ρxy(B, T) magnetoresistances have been investigated experimentally as a function of the transverse magnetic field B up to 12 T in the temperature range T = 1.8–80 K in n-InGaAs/GaAs nanostructures with single and double strongly-coupled quantum wells with different barrier widths. It is shown that there is a critical value of magnetic field in the vicinity of ωcτ ≅ 1 where the scaling ratio ρxx ∝|BBC|T –κ is valid which indicates the observation of a genuine insulator–quantum Hall liquid phase transition. It was found that the value of the critical exponent κ depends on the width of the barrier between the double quantum wells. The nature of such a behavior is discussed.

PACS: 73.21.Fg Quantum wells;
PACS: 73.40.–c Electronic transport in interface structures;
PACS: 73.43.Qt Magnetoresistance.

Key words: double quantum wells, quantum magneto-transport, insulator–quantum Hall transition.

Published online: February 24, 2017

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