The role of small-angle electron-electron scattering in transverse magnetic focusing experiment

TL;DR

This paper highlights the importance of small-angle electron-electron scattering in transverse magnetic focusing experiments and introduces a model to accurately extract the e-e scattering length from experimental data.

Contribution

It presents a phenomenological model linking sample geometry to scattering effects, enabling precise measurement of the e-e scattering length in TMF experiments.

Findings

Small-angle e-e scattering significantly influences TMF measurements.

Sample geometry affects the role of scattering in TMF.

The proposed model accurately fits experimental data.

Abstract

We demonstrate the crucial role of small-angle scattering in transverse magnetic focusing (TMF) in ballistic GaAs/AlGaAs heterostructures. Measurements in various samples show that the role significantly depends on their geometry. We propose a phenomenological model parameterizing this dependence with the angular acceptance of the detecting contact. This model is consistent with the diversity of experimental data and therefore enables accurate extraction of the key characteristic of inter-electron (e-e) interaction $\unicode{x2013}$ the e-e scattering length $\unicode{x2013}$ from TMF experiment, thus turning it into a uniquely effective tool for studying e-e scattering.