Interaction Effects and Pseudogap in Two-Dimensional Lateral Tunnel Junctions

TL;DR

This study investigates the tunneling behavior and pseudogap phenomena in two-dimensional lateral tunnel junctions, revealing the influence of Coulomb interactions and magnetic fields on the electronic density of states.

Contribution

It provides experimental evidence of a Coulomb energy-scale pseudogap in 2D tunnel junctions and explores its modification by in-plane magnetic fields.

Findings

Detection of a Coulomb pseudogap in TDOS

Persistence of pseudogap into quantum Hall regime

Modification of pseudogap by in-plane magnetic field

Abstract

Tunneling characteristics of a two-dimensional lateral tunnel junction (2DLTJ) are reported. A pseudogap on the order of Coulomb energy is detected in the tunneling density of states (TDOS) when two identical two-dimensional electron systems are laterally separated by a thin energy barrier. The Coulombic pseudogap remains robust well into the quantum Hall regime until it is overshadowed by the cyclotron gap in the TDOS. The pseudogap is modified by in-plane magnetic field, demonstrating a non-trivial effect of in-plane magnetic field on the electron-electron interaction.