We present experimental results of transverse electron focusing measurements performed on an n-type GaAs based mesoscopic device consisting of one-dimensional (1D) quantum wires as injector and detector. We show that non-adiabatic injection of 1D electrons at a conductance of e2/h results in a single first focusing peak, which on gradually increasing the injector conductance up to 2e2/h , produces asymmetric two sub-peaks in the first focusing peak, each sub-peak representing the population of spin-state arising from the spatially separated spins in the injector. Further increasing the conductance flips the spin-states in the 1D channel thus reversing the asymmetry in the sub-peaks. On applying a source-drain bias, the spin-gap, so obtained, can be resolved thus providing evidence of exchange interaction induced spin polarisation in the 1D systems.
@article{arxiv.1707.04575,
title = {Direct observation of exchange-driven spin interactions in one-dimensional system},
author = {Chengyu Yan and Sanjeev Kumar and Kalarikad Thomas and Michael Pepper and Patrick See and Ian Farrer and David Ritchie and J. P. Griffiths and G. A. C. Jones},
journal= {arXiv preprint arXiv:1707.04575},
year = {2017}
}