Detecting the tunneling rates for strongly interacting fermions on optical lattices

Journal Article · Thu Apr 15 00:00:00 EDT 2010 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.81.043630· OSTI ID:21408687

Anfossi, Alberto ^[1]; Barbiero, Luca; Montorsi, Arianna ^[1]

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1. Dipartimento di Fisica del Politecnico, corso Duca degli Abruzzi 24, I-10129, Torino (Italy)

Strongly interacting fermionic atoms on optical lattices are studied through a Hubbard-like model Hamiltonian, in which tunneling rates of atoms and molecules between neighboring sites are assumed to be different. In the limit of large on-site repulsion U, the model is shown to reproduce the t-J Hamiltonian, in which the J coefficient of the Heisenberg term depends on the particle-assisted tunneling rate g: explicitly, J=4g{sup 2}/U. At half-filling, g drives a crossover from a Brinkman-Rice paramagnetic insulator of fully localized atoms (g=0) to the antiferromagnetic Mott insulator of the standard Hubbard case (g=t). This is observed already in the number of doubly occupied sites under the intermediate coupling regime, thus providing a criterion for extracting from measurements the effective value of g.

• OSTI ID: 21408687
• Journal Information: Physical Review. A, Vol. 81, Issue 4; Other Information: DOI: 10.1103/PhysRevA.81.043630; (c) 2010 The American Physical Society; ISSN 1050-2947
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ANTIFERROMAGNETISM
ATOMS
FERMIONS
HAMILTONIANS
INTERMEDIATE COUPLING
MOLECULES
PARAMAGNETISM
TUNNEL EFFECT
COUPLING
MAGNETISM
MATHEMATICAL OPERATORS
QUANTUM OPERATORS