Tunneling into a two-dimensional electron system in a strong magnetic field

TL;DR

This paper studies the electron tunneling properties in a strongly interacting two-dimensional electron system under high magnetic fields, revealing suppressed spectral weight near zero energy and proposing a model for low-energy behavior.

Contribution

It introduces a theoretical model explaining the low-energy spectral weight behavior in a 2D electron system with Coulomb interactions at high magnetic fields.

Findings

Spectral weight is suppressed near zero energy.

Maximum spectral weight occurs around 0.2 e^2/εl_c.

Spectral weight decays exponentially at higher energies.

Abstract

We investigate the properties of the one-electron Green's function in an interacting two-dimensional electron system in a strong magnetic field, which describes an electron tunneling into such a system. From finite-size diagonalization, we find that its spectral weight is suppressed near zero energy, reaches a maximum at an energy of about $0.2e^{2}/\epsilon l_{c}$, and decays exponentially at higher energies. We propose a theoretical model to account for the low-energy behavior. For the case of Coulomb interactions between the electrons, at even-denominator filling factors such as $\nu=1/2$, we predict that the spectral weight varies as $e^{-\omega_0/|\omega|}$, for $\omega\rightarrow 0$.