2024/07/16 by Jens Samland, Nicola Wurz, Samland, J. +5 · 1 citation
Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #FOS: Physical sciences #Quantum Gases (cond-mat.quant-gas) #Quantum, superfluid, helium dynamics
paper · pdf · doi:10.48550/arxiv.2407.11863
openalex publication_date 2024/07/16 · openalex created_date 2024/08/18 · openalex updated_date 2026/07/28
We measure the equation of state in a bilayer Hubbard system for different ratios of the two tunnelling amplitudes t_⊥ /t. From the equation of state we deduce the compressibility and observe its dependency on t_⊥ /t. Moreover, we infer thermodynamic number fluctuations from the equation of state by employing the fluctuation-dissipation theorem. By comparing the thermodynamic with local density fluctuations, we find that non-local density fluctuations in our bilayer Hubbard system become more prominent for higher t_⊥ /t in the low filling regime. To validate our measurements, we compare them to Determinant Quantum Monte Carlo simulations of a bilayer Hubbard system with 6×6 lattice sites per layer.