Portal de Periódicos da CAPES

Universal dynamics of a degenerate unitary Bose gas

2014; Nature Portfolio; Volume: 10; Issue: 2 Linguagem: Inglês

10.1038/nphys2850

1745-2481

Philip Makotyn, Catherine Klauss, David Goldberger, Eric Cornell, D. S. Jin,

Quantum many-body systems

Ultracold atoms could help in understanding the physics of strongly interacting many-body systems, but the creation of degenerate Bose gases at unitarity has been hampered by the losses. An experiment overcomes these problems and investigates the time evolution of a unitary Bose gas. From neutron stars to high-temperature superconductors, strongly interacting many-body systems at or near quantum degeneracy are a rich source of intriguing phenomena. The microscopic structure of the first-discovered quantum fluid, superfluid liquid helium, is difficult to access owing to limited experimental probes. Although an ultracold atomic Bose gas with tunable interactions (characterized by its scattering length, a) had been proposed as an alternative strongly interacting Bose system1,2,3,4,5,6,7,8, experimental progress9,10,11,12 has been limited by its short lifetime. Here we present time-resolved measurements of the momentum distribution of a Bose-condensed gas that is suddenly jumped to unitarity, where . Contrary to expectation, we observe that the gas lives long enough to permit the momentum to evolve to a quasi-steady-state distribution, consistent with universality, while remaining degenerate. Investigations of the time evolution of this unitary Bose gas may lead to a deeper understanding of quantum many-body physics.