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arXiv · 2005.08308

Anomalous spin-charge separation in a driven Hubbard system

Hongmin Gao·Jonathan R. Coulthard·Dieter Jaksch·Jordi Mur-Petit
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Abstract

Spin-charge separation (SCS) is a striking manifestation of strong correlations in low-dimensional quantum systems, whereby a fermion splits into separate spin and charge excitations that travel at different speeds. Here, we demonstrate that periodic driving enables control over SCS in a Hubbard system near half-filling. In one dimension, we predict analytically an exotic regime where charge travels slower than spin and can even become 'frozen', in agreement with numerical calculations. In two dimensions, the driving slows both charge and spin, and leads to complex interferences between single-particle and pair-hopping processes.

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Hongmin Gao, Jonathan R. Coulthard, Dieter Jaksch, Jordi Mur-Petit. 2020-05-13. Anomalous spin-charge separation in a driven Hubbard system. https://doi.org/10.1103/physrevlett.125.195301

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