Many-body quench dynamics in trapped-ion quantum simulators*

Trapped-ion quantum simulators are pristine platforms to study out-of-equilibrium many-body systems. We engineer such a simulator embedded with tunable long-range spin-spin interaction using qubits encoded in the hyperfine clock state of $^{\mathrm{171}}$Yb$^{\mathrm{+}}$ atomic ions. With precise laser control, long coherence times, and individual single-shot readout capability, we explore the out-of-equilibrium dynamics after a quantum quench in a transverse Ising Hamiltonian. We first investigate the domain-wall confinement effect on the spin dynamics after the sudden quench. We observe that the spreading of correlations is confined since low-energy excitations are bounded to meson-like quasiparticles. We further study how a weakly nonintegrable many-body system thermalizes after a quantum quench by looking at the temporal fluctuations of the spins [1]. Such fluctuations are exponentially suppressed by increasing the system size as a result of many-body dephasing. We also introduce EIT cooling to simultaneously cool many motional modes of a long chain of ions across a large bandwidth, which is particularly useful for low-frequency modes. [1] H. B. Kaplan, et al., arXiv: 2001.02477 (2020).