Observation of spatial charge and spin correlations in the 2D Fermi-Hubbard model
Abstract
Strong electron correlations lie at the origin of high-temperature superconductivity. Its essence is believed to be captured by the Fermi-Hubbard model of repulsively interacting fermions on a lattice. Here we report on the site-resolved observation of charge and spin correlations in the two-dimensional (2D) Fermi-Hubbard model realized with ultracold atoms. Antiferromagnetic spin correlations are maximal at half-filling and weaken monotonically upon doping. At large doping, nearest-neighbor correlations between singly charged sites are negative, revealing the formation of a correlation hole, the suppressed probability of finding two fermions near each other. As the doping is reduced, the correlations become positive, signaling strong bunching of doublons and holes, in agreement with numerical calculations. The dynamics of the doublon-hole correlations should play an important role for transport in the Fermi-Hubbard model.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Sep 16, 2016
- Source ID
- 10.1126/science.aag3349
Entities
People
- Ehsan Khatami
- Hao Zhang
- Katherine R. Lawrence
- Lawrence W. Cheuk
- Marcos Rigol
- Martin W. Zwierlein
- Matthew A. Nichols
- Melih Okan
- Nandini Trivedi
- Thereza Paiva
Organizations
- Air Force Office of Scientific Research
- David and Lucile Packard Foundation
- Federal University of Rio de Janeiro
- Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro
- Hertz Foundation
- Massachusetts Institute of Technology
- National Council for Scientific and Technological Development
- National Science Foundation
- Office of Naval Research
- Ohio State University
- Pennsylvania State University
- San José State University
- Simons Foundation