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Title: Spin transport in a Mott insulator of ultracold fermions
Strongly correlated materials are expected to feature unconventional transport properties, such that charge, spin, and heat conduction are potentially independent probes of the dynamics. In contrast to charge transport, the measurement of spin transport in such materials is highly challenging. We observed spin conduction and diffusion in a system of ultracold fermionic atoms that realizes the half-filled Fermi-Hubbard model. For strong interactions, spin diffusion is driven by super-exchange and doublon-hole–assisted tunneling, and strongly violates the quantum limit of charge diffusion. The technique developed in this work can be extended to finite doping, which can shed light on the complex interplay between spin and charge in the Hubbard model.  more » « less
Award ID(s):
1734011
PAR ID:
10099314
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Science
Volume:
363
Issue:
6425
ISSN:
0036-8075
Page Range / eLocation ID:
383 to 387
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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