Estimating strong correlations in optical lattices
arXiv:1606.01913 · doi:10.1103/PhysRevA.94.053628
Abstract
Ultra-cold atoms in optical lattices provide one of the most promising platforms for analog quantum simulations of complex quantum many-body systems. Large-size systems can now routinely be reached and are already used to probe a large variety of different physical situations, ranging from quantum phase transitions to artificial gauge theories. At the same time, measurement techniques are still limited and full tomography for these systems seems out of reach. Motivated by this observation, we present a method to directly detect and quantify to what extent a quantum state deviates from a local Gaussian description, based on available noise correlation measurements from in-situ and time-of-flight measurements. This is an indicator of the significance of strong correlations in ground and thermal states, as Gaussian states are precisely the ground and thermal states of non-interacting models. We connect our findings, augmented by numerical tensor network simulations, to notions of equilibration, disordered systems and the suppression of transport in Anderson insulators.
7 pages, 2 figures
References in corpus (12)
- Many-Body Physics with Ultracold Gases
- Single-Atom Resolved Fluorescence Imaging of an Atomic Mott Insulator
- Efficient quantum state tomography
- Spatial quantum noise interferometry in expanding ultracold atom clouds
- Exact relaxation in a class of non-equilibrium quantum lattice systems
- Generalized Thermalization in an Integrable Lattice System
- A cold-atom quantum simulator for SU(2) Yang-Mills lattice gauge theory
- Quantifying the non-Gaussian character of a quantum state by quantum relative entropy
- Emergence of coherence and the dynamics of quantum phase transitions
- Estimating entanglement measures in experiments
- When are correlations quantum? -- Verification and quantification of entanglement by simple measurements
- Directly estimating non-classicality