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arXiv · 1707.04575

Direct observation of exchange-driven spin interactions in one-dimensional system

Chengyu Yan·Sanjeev Kumar·Kalarikad Thomas·Michael Pepper·Patrick See·Ian Farrer·David Ritchie·J. P. Griffiths·G. A. C. Jones
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Abstract

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 e$^2$/h results in a single first focusing peak, which on gradually increasing the injector conductance up to 2e$^2$/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.

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Chengyu Yan, Sanjeev Kumar, Kalarikad Thomas, Michael Pepper, Patrick See, Ian Farrer, David Ritchie, J. P. Griffiths, G. A. C. Jones. 2017-07-14. Direct observation of exchange-driven spin interactions in one-dimensional system. https://doi.org/10.1063/1.4989374

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