Dynamical structure factor of one-dimensional Bose gases: experimental signatures of beyond-Luttinger liquid physics

Abstract

Interactions are known to have dramatic effects on bosonic gases in one dimension (1D). Not only does the ground state transform from a condensate-like state to an effective Fermi sea, but new fundamental excitations, which do not have any higher-dimensional equivalents, are predicted to appear. In this work, we trace these elusive excitations via their effects on the dynamical structure factor of 1D strongly-interacting Bose gases at low temperature. An array of 1D Bose gases is obtained by loading a ${}^{87}$Rb condensate in a 2D lattice potential. The dynamical structure factor of the system is probed by energy deposition through low-momentum Bragg excitations. The experimental signals are compared to recent theoretical predictions for the dynamical structure factor of the Lieb-Liniger model at $T>0$. Our results demonstrate that the main contribution to the spectral widths stems from the dynamics of the interaction-induced excitations in the gas, which cannot be described by the Luttinger liquid theory.

References in corpus (7)

• A one-dimensional liquid of fermions with tunable spin
• Bosonizing one-dimensional cold atomic gases
• Quantum transport through a Tonks-Girardeau gas
• Dynamical density-density correlations in the one-dimensional Bose gas
• Exploring correlated 1D Bose gases from the superfluid to the Mott-insulator state by inelastic light scattering
• Polarizability and dynamic structure factor of the one-dimensional Bose gas near the Tonks-Girardeau limit at finite temperatures
• Spatial nonlocal pair correlations in a repulsive 1D Bose gas

Cited by in corpus (5)

• Dynamic structure factor and drag force in a one-dimensional strongly-interacting Bose gas at finite temperature
• Local correlations in the attractive 1D Bose gas: from Bethe ansatz to the Gross-Pitaevskii equation
• Dynamical structure factor of one-dimensional hard rods
• Long time thermal asymptotics of nonlinear Luttinger liquid from inverse scattering
• Energy and momentum transfer in one-dimensional trapped gases by stimulated light scattering