Interaction correction to conductivity of Al$_x$Ga$_{1-x}$As/GaAs double quantum well heterostructures near the balance

TL;DR

This study experimentally investigates the electron-electron interaction quantum correction to the conductivity in double quantum well heterostructures, finding that the correction is consistent regardless of whether the structure is balanced or only one well is occupied.

Contribution

It provides the first reliable measurement of the diffusion part of the interaction correction in balanced and unbalanced double quantum well structures.

Findings

Interaction correction is similar in both regimes.

No resonant behavior observed in the correction.

Experimental analysis of temperature and magnetic field dependence.

Abstract

The electron-electron interaction quantum correction to the conductivity of the gated double well Al$_x$Ga$_{1-x}$As/GaAs structures is investigated experimentally. The analysis of the temperature and magnetic field dependences of the conductivity tensor allows us to obtain reliably the diffusion part of the interaction correction for the regimes when the structure is balanced and when only one quantum well is occupied. The surprising result is that the interaction correction does not reveal resonant behavior; it is practically the same for both regimes.