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arXiv · 0803.0744

Charge Fractionalization in nonchiral Luttinger systems

Karyn Le Hur·Bertrand I. Halperin·Amir Yacoby
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Abstract

One-dimensional metals, such as quantum wires or carbon nanotubes, can carry charge in arbitrary units, smaller or larger than a single electron charge. However, according to Luttinger theory, which describes the low-energy excitations of such systems, when a single electron is injected by tunneling into the middle of such a wire, it will tend to break up into separate charge pulses, moving in opposite directions, which carry definite fractions $f$ and $(1-f)$ of the electron charge, determined by a parameter $g$ that measures the strength of charge interactions in the wire. (The injected electron will also produce a spin excitation, which will travel at a different velocity than the charge excitations.) Observing charge fractionalization physics in an experiment is a challenge in those (nonchiral) low-dimensional systems which are adiabatically coupled to Fermi liquid leads. We theoretically discuss a first important step towards the observation of charge fractionalization in quantum wires based on momentum-resolved tunneling and multi-terminal geometries, and explain the recent experimental results of H. Steinberg {\it et al.}, Nature Physics {\bf 4}, 116 (2008).

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Karyn Le Hur, Bertrand I. Halperin, Amir Yacoby. 2008-03-05. Charge Fractionalization in nonchiral Luttinger systems. https://arxiv.org/abs/0803.0744

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