Science

Spin and charge go their separate ways

Jelena Stajic

Published Jan 9, 2020• 0 citations

Abstract

Quantum Simulation Strongly interacting chains of fermions are predicted to exhibit two types of collective excitations: spinons, which carry only spin, and holons, which carry only charge. These excitations move at different velocities. Signatures of this so-called spin-charge separation have been observed in solid-state systems, but obtaining direct dynamical evidence is tricky. With this goal in mind, Vijayan et al. perturbed a chain of ultracold interacting fermions housed in a one-dimensional optical lattice by removing one of the atoms. This gave rise to two independent excitations, which the researchers identified as spinons and holons using a quantum gas microscope. Science , this issue p. [186][1] [1]: /lookup/doi/10.1126/science.aay2354

DOI: 10.1126/science.367.6474.158-d

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