A quantum many-body spin system in an optical lattice clock

• Main Authors: Martin, M. J, Bishof, M, Swallows, M. D, Zhang, X, Benko, C, von-Stecher, J, Gorshkov, A. V, Rey, A. M, Ye, Jun
• Format: Journal Article
• Language: English
• Published: 27-12-2012
• Subjects: Physics - Atomic Physics; Physics - Quantum Gases; Physics - Quantum Physics
• DOI: 10.48550/arxiv.1212.6291

Science 341, 632 - 636 (2013) Strongly interacting quantum many-body systems are fundamentally compelling
and ubiquitous in science. However, their complexity generally prevents exact
solutions of their dynamics. Precisely engineered ultracold atomic gases are
emerging as a powerful tool to unravel these challenging physical problems.
Here we present a new laboratory for the study of many-body effects: strongly
interacting two-level systems formed by the clock states in ^{87}$Sr, which
are used to realize a neutral atom optical clock that performs at the highest
level of optical-atomic coherence and with precision near the limit set by
quantum fluctuations. Our measurements of the collective spin evolution reveal
signatures of many-body dynamics, including beyond-mean-field effects. We
derive a many-body Hamiltonian that describes the experimental observation of
severely distorted lineshapes, atomic spin coherence decay, density-dependent
frequency shifts, and correlated quantum spin noise. These investigations open
the door to exploring quantum many-body effects and entanglement in quantum
systems with optical energy splittings, using highly coherent and precisely
controlled optical lattice clocks.