Tunable nanomagnetism in moderately cold fermions on optical lattices

Abstract

Localized defects, unavoidable in real solids, may be simulated in (generically defect-free) cold-atom systems, e.g., via modifications of the optical lattice. We study the Hubbard model on a square lattice with single impurities, pairs of nearby impurities, or lines of impurities using numerically exact determinantal quantum Monte Carlo simulations. In all cases, correlations on the "impurity" sites are enhanced either by larger on-site interactions or by a reduced coupling to the environment. We find highly nontrivial magnetic correlations, which persist at elevated temperatures and should be accessible in cold-atom systems with current experimental techniques. With improved cooling techniques, these features could be followed towards generic quantum antiferromagnetism in the homogeneous limit. More generally, tunable crossing points between different correlation functions could be used, in a quantum steelyard balance setup, as robust thermometers.

arXiv comment8 pages, 7 figures, version accepted for publication by Phys. Rev. A

References in corpus (35)

• A quantum gas microscope - detecting single atoms in a Hubbard regime optical lattice
• A Mott insulator of fermionic atoms in an optical lattice
• Creating, moving and merging Dirac points with a Fermi gas in a tunable honeycomb lattice
• Single-Spin Addressing in an Atomic Mott Insulator
• Observation of Fermi Polarons in a Tunable Fermi Liquid of Ultracold Atoms
• Fermi-Hubbard physics with atoms in an optical lattice
• Defects in correlated metals and superconductors
• Short-range quantum magnetism of ultracold fermions in an optical lattice
• A trapped single ion inside a Bose-Einstein condensate
• Collective Oscillations of an Imbalanced Fermi Gas: Axial Compression Modes and Polaron Effective Mass
• Dynamics of a cold trapped ion in a Bose-Einstein condensate
• Anderson localization in Bose-Einstein condensates
• Strongly interacting bosons in a disordered optical lattice
• Quantitative Determination of Temperature in the Approach to Magnetic Order of Ultracold Fermions in an Optical Lattice
• Antiferromagnetic Order of Strongly Interacting Fermions in a Trap: Real-Space Dynamical Mean-Field Analysis
• Fermions in 2D Optical Lattices: Temperature and Entropy Scales for Observing Antiferromagnetism and Superfluidity
• Mott transition of fermionic atoms in a three-dimensional optical trap
• Controlling and Detecting Spin Correlations of Ultracold Atoms in Optical lattices
• Probing nearest-neighbor correlations of ultracold fermions in an optical lattice
• Local Enhancement of Antiferromagnetic Correlations by Nonmagnetic Impurities
• Néel transition of lattice fermions in a harmonic trap: a real-space DMFT study
• Momentum-dependent pseudogaps in the half-filled two-dimensional Hubbard model
• Single Impurity In Ultracold Fermi Superfluids
• Universal probes for antiferromagnetic correlations and entropy in cold fermions on optical lattices
• Bound states of a localized magnetic impurity in a superfluid of paired ultracold fermions
• Towards a Classification of the Effects of Disorder on Materials Properties
• Efficiency of quantum Monte Carlo impurity solvers for dynamical mean-field theory
• Anderson impurity in the one-dimensional Hubbard model on finite size systems
• Mott transitions in the half-filled SU(2M) symmetric Hubbard model
• Self-localization of a small number of Bose particles in a superfluid Fermi system
• Interaction effects between impurities in low dimensional spin-1/2 antiferromagnets
• Formation of magnetic impurities and pair-breaking effect in a superfluid Fermi gas
• Quantum Monte Carlo simulations of antiferromagnetism in ultracold fermions on optical lattices within real-space dynamical mean-field theory
• Discriminating antiferromagnetic signatures in ultracold fermions by tunable geometric frustration
• Interaction-induced localization of fermionic mobile impurities in a Larkin-Ovchinnikov superfluid