Anomalous spin-dependent behaviour of one-dimensional subbands

TL;DR

This paper uncovers a new electron interaction effect in GaAs/AlGaAs quantum wires, revealing significant spin-dependent energy changes across various magnetic fields, expanding understanding of spin-related phenomena in low-dimensional systems.

Contribution

It demonstrates a novel spin-dependent interaction effect affecting energy states in quantum wires, observed through DC-bias spectroscopy across a wide range of magnetic fields.

Findings

Large abrupt energy changes in spin-down states

Effect observed at all magnetic fields from 0 to 16T

Interaction effects influence the energy spectrum beyond the 0.7 Structure

Abstract

We report a new electron interaction effect in GaAs/AlGaAs quantum wires. Using DC-bias spectroscopy, we show that large and abrupt changes occur to the energies of spin-down (lower energy) states as they populate. The effect is not observed for spin-up energy states. At B=0, interactions have a pronounced effect, in the form of the well-known 0.7 Structure. However, our new results show that interactions strongly affect the energy spectrum at all magnetic fields, from 0 to 16T, not just in the vicinity of the 0.7 Structure.