We study the time evolution of ultracold atoms in an accelerated optical lattice. For a Bose-Einstein condensate with a narrow quasimomentum distribution in a shallow optical lattice the decay of the survival probability in the ground band has a steplike structure. In this regime we establish a connection between the wave-function-renormalization parameter Z introduced by P. Facchi, H. Nakazato, and S. Pascazio [Phys. Rev. Lett. 86, 2699 (2001)] to characterize nonexponential decay and the phenomenon of resonantly enhanced tunneling, where the decay rate is peaked for particular values of the lattice depth and the accelerating force.
Wave-function-renormalization effects in resonantly enhanced tunneling / N., Lörch; F., Pepe; H., Lignier; D., Ciampini; R., Mannella; O., Morsch; E., Arimondo; P., Facchi; G., Florio; S., Pascazio; Wimberger, Sandro Marcel. - In: PHYSICAL REVIEW A. - ISSN 1050-2947. - 85:5(2012), p. 053602. [10.1103/PhysRevA.85.053602]
Wave-function-renormalization effects in resonantly enhanced tunneling
WIMBERGER, Sandro Marcel
2012-01-01
Abstract
We study the time evolution of ultracold atoms in an accelerated optical lattice. For a Bose-Einstein condensate with a narrow quasimomentum distribution in a shallow optical lattice the decay of the survival probability in the ground band has a steplike structure. In this regime we establish a connection between the wave-function-renormalization parameter Z introduced by P. Facchi, H. Nakazato, and S. Pascazio [Phys. Rev. Lett. 86, 2699 (2001)] to characterize nonexponential decay and the phenomenon of resonantly enhanced tunneling, where the decay rate is peaked for particular values of the lattice depth and the accelerating force.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
