The experimental work presented in this thesis studies and characterizes decoherence of excited matter-wave solitons, known as breathers, in neutral lithium-7 BECs. Motivated by the rich pool of theoretical predictions for beyond mean-field physics, and recent work in our lab which experimentally realized the production of breathers, we study the lifetime and decay of breathers in a one-dimensional (1D) wave guide. We report measurements of decoherence and dissociation of breathers in a quasi- 1D geometry, and attribute the dissociation features to three-body loss by comparing against numerical results from the 1D Gross-Pitaevskii (GP) simulations in the mean- field approximation. We find that in the low atomic density regime for breathers, breathers no longer dissociate and deviate from the GP simulation results. In this regime, the breather damps out and embodies signatures of relaxation associated with beyond mean-field number fluctuations.The experimental work presented in this thesis studies and characterizes decoherence of excited matter-wave solitons, known as breathers, in neutral lithium-7 BECs. Motivated by the rich pool of theoretical predictions for beyond mean-field physics, and recent work in our lab which experimentally realized the production of breathers, we study the lifetime and decay of breathers in a one-dimensional (1D) wave guide. We report measurements of decoherence and dissociation of breathers in a quasi- 1D geometry, and attribute the dissociation features to three-body loss by comparing against numerical results from the 1D Gross-Pitaevskii (GP) simulations in the mean- field approximation. We find that in the low atomic density regime for breathers, breathers no longer dissociate and deviate from the GP simulation results. In this regime, the breather damps out and embodies signatures of relaxation associated with beyond mean-field number fluctuations.

Jul 9, 20240 citations

$^{7}$ Li BEC in a millimeter-scale Ioffe-Pritchard trap$^{7}$Li BEC in a millimeter-scale Ioffe-Pritchard trap

Mingchang Liu, Ruquan Wang, F. Minardi +1 more

Bulletin of the American Physical SocietyMay 17, 20060 citations

BEC and the New World of Coherent Matter Waves

Allan Griffin

Springer eBooksJan 1, 20022 citations

Superfluid Fermi Gas in Optical Lattices: Self-Trapping, Stable, Moving Solitons and Breathers

Ju-Kui Xue, Ai‐Xia Zhang

We predict the existence of self-trapping, stable, moving solitons and breathers of Fermi wave packets along the Bose-Einstein condensation (BEC)-BCS crossover in one dimension (1D), 2D, and 3D optical lattices. The dynamical phase diagrams for self-trapping, solitons, and breathers of the Fermi matter waves along the BEC-BCS crossover are presented analytically and verified numerically by directly solving a discrete nonlinear Schrödinger equation. We find that the phase diagrams vary greatly along the BEC-BCS crossover; the dynamics of Fermi wave packet are different from that of Bose wave packet.We predict the existence of self-trapping, stable, moving solitons and breathers of Fermi wave packets along the Bose-Einstein condensation (BEC)-BCS crossover in one dimension (1D), 2D, and 3D optical lattices. The dynamical phase diagrams for self-trapping, solitons, and breathers of the Fermi matter waves along the BEC-BCS crossover are presented analytically and verified numerically by directly solving a discrete nonlinear Schrödinger equation. We find that the phase diagrams vary greatly along the BEC-BCS crossover; the dynamics of Fermi wave packet are different from that of Bose wave packet.

Physical Review LettersOct 28, 200855 citations

Efficient loading of a BEC into a matter wave resonator

Vyacheslav Lebedev, Changhyun Ryu, M. G. Boshier

Bulletin of the American Physical SocietyJun 12, 20150 citations

Formation of a Matter-Wave Breather in a

^7 \mathrm{Li}

BEC

^{7}

Li BEC in a millimeter-scale Ioffe-Pritchard trap