Evidence of Skyrmion excitations about $\nu =1$ in n-Modulation Doped Single Quantum Wells by Inter-band Optical Transmission

TL;DR

This study provides experimental evidence for Skyrmion excitations in a two-dimensional electron gas at filling factor , revealed through changes in spin polarization measured by inter-band optical transmission in quantum wells.

Contribution

The paper demonstrates the presence of Skyrmion excitations near  in quantum wells, highlighting the dominance of exchange energy over Zeeman energy in this regime.

Findings

Rapid decay of spin polarization off 

Magneto-absorption spectra reveal spin state occupancy

Evidence supports Skyrmion excitations in quantum Hall regime

Abstract

We observe a dramatic reduction in the degree of spin-polarization of a two-dimensional electron gas in a magnetic field when the Fermi energy moves off the mid-point of the spin-gap of the lowest Landau level, $\nu=1$. This rapid decay of spin alignment to an unpolarized state occurs over small changes to both higher and lower magnetic field. The degree of electron spin polarization as a function of $\nu$ is measured through the magneto-absorption spectra which distinguish the occupancy of the two electron spin states. The data provide experimental evidence for the presence of Skyrmion excitations where exchange energy dominates Zeeman energy in the integer quantum Hall regime at $\nu=1$.