Abstract:
:It has been a long-sought goal of quantum simulation to find answers to outstanding questions in condensed-matter physics. A famous example is finding the ground state and the excitations of the two-dimensional (2D) Hubbard model with strong repulsion below half-filling. This system is a doped antiferromagnet and is of great interest because of its possible relation to high-[Formula: see text] superconductors. Theoretically, the fermion excitations of this model are believed to split up into holons and spinons, and a moving holon is believed to leave behind it a string of "wrong" spins that mismatch with the antiferromagnetic background. Here, we show that the properties of the ground-state wavefunction and the holon excitation of the 2D Hubbard model can be revealed in unprecedented detail by using the imaging and the interference technique in atomic physics. They allow one to reveal the Marshall sign of the doped antiferromagnet. The region of wrong Marshall sign indicates the location of the holon string.
journal_name
Proc Natl Acad Sci U S Aauthors
Ho TLdoi
10.1073/pnas.2004268117subject
Has Abstractpub_date
2020-10-20 00:00:00pages
26141-26144issue
42eissn
0027-8424issn
1091-6490pii
2004268117journal_volume
117pub_type
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