Effect of the angular momentum on the magnitude of the current in magneto-tunnelling spectroscopy of quantum dots

TL;DR

This study investigates how angular momentum influences the current magnitude in magneto-tunnelling spectroscopy of quantum dots, revealing non-monotonic behaviors and tunnelling suppression related to magnetic field effects on quantum states.

Contribution

It provides new experimental and theoretical insights into the role of angular momentum in quantum dot tunnelling under magnetic fields, highlighting the impact on current amplitudes.

Findings

Current peak amplitudes vary non-monotonically with magnetic field.

Magnetic field suppresses tunnelling through states with angular momentum parallel to the field.

Magnetic field can completely inhibit tunnelling for certain angular momentum states.

Abstract

We present an experimental and theoretical study of electron tunnelling through quantum dots which focusses the attention on the amplitude of the current peaks as a function of magnetic field. We demonstrate that the amplitudes of the current peaks in the tunnelling spectra show a dramatically different behaviour as a function of the magnetic field, depending on the angular momentum of the dot state through which tunnelling occurs. This is seen in the non-monotonic behaviour of the current amplitude in magnetic field. Furthermore, the magnetic field severely hinders tunnelling through states with angular momentum parallel to the field, and in some cases it makes it altogether impossible. This type of investigation allows us to directly probe the details of the confined wave functions of the quantum dot.