RT Journal Article
SR Electronic
T1 Recurrences in an isolated quantum many-body system
JF Science
JO Science
FD American Association for the Advancement of Science
SP 307
OP 310
DO 10.1126/science.aan7938
VO 360
IS 6386
A1 Rauer, Bernhard
A1 Erne, Sebastian
A1 Schweigler, Thomas
A1 Cataldini, Federica
A1 Tajik, Mohammadamin
A1 Schmiedmayer, Jörg
YR 2018
UL http://science.sciencemag.org/content/360/6386/307.abstract
AB A finite isolated system should return almost to its initial state if it evolves for long enough. For a large system, “long enough” is often unfeasibly long. Rauer et al. found just the right conditions to observe the recurrence of the initial state in a system of two one-dimensional superfluids with thousands of atoms in each. The superfluids were initially coupled—locking their quantum mechanical phases together—and then allowed to evolve independently. After the uncoupling, the researchers observed their phases regaining coherence two more times.Science, this issue p. 307The complexity of interacting quantum many-body systems leads to exceedingly long recurrence times of the initial quantum state for all but the smallest systems. For large systems, one cannot probe the full quantum state in all its details. Thus, experimentally, recurrences can only be determined on the level of the accessible observables. Realizing a commensurate spectrum of collective excitations in one-dimensional superfluids, we demonstrate recurrences of coherence and long-range order in an interacting quantum many-body system containing thousands of particles. Our findings will enable the study of the coherent dynamics of large quantum systems even after they have reached a transient thermal-like state.