Abstract

One-dimensional (1D) electron systems are described by the Tomonaga-Luttinger liquid (TLL) model. This gives rise to phenomena such as spin-charge separation and the zero-bias anomaly [1]. These predictions have been experimentally observed in GaAs/AlGaAs heterostructure devices by measuring the tunnelling between an array of 1D wires and a 2DEG [2]. The aim of our project is to go beyond the TLL model, which assumes wires of infinite length, by studying shorter wires (< 10um) in which the edge effects must be accounted for. It has been theoretically predicted that higher order excitations should appear in shorter wires [3]. I present recent data showing promising signs of these excitations.

[1] Deshpande et al. Electron liquids and solids in one dimension, Nature 464, p.209-216 (2010) [2] Jompol et al. Probing spin-charge separation in a Tomonaga-Luttinger liquid, Science 325, p.597-601 (2009) [3] Tsyplyatyev et al. Hierarchy of Modes in an Interacting One-Dimensional System, Phys Rev Lett 114, 196401 (2015)