Interplay of attractive interactions and trap anisotropy in Bose-Einstein condensates
Abstract/Contents
- Abstract
- We evaporatively cool attractively interacting bosonic 7Li in a quasi-one dimensional (quasi-1D) trap to well below the non-interacting particle condensation temperature for our trap but do not observe conventional Bose-Einstein condensation (BEC). Rather than the macroscopic occupation of a single quantum state, for our coldest clouds we observe densities far above the minimum required for quantum degeneracy and widths many times greater than the non-interacting and Gross-Pitaevskii (GP) predictions. We quantify the discrepancies, which together indicate the formation of clouds with multiply macroscopically occupied trap states. We hypothesize that the specific combination of a quasi-1D anisotropic trap and attractively interacting atoms might provide for many-body states that reside in manifolds of nearly degenerate states, which could inhibit conventional BEC. This idea is probed theoretically using the two-body interaction Hamiltonian to extend the single-mode many-body mean-field GP formalism to allow for atom scattering between two single-particle trap modes. We find that many odd-relative parity energy-adjacent single-particle state pairs exhibit sizable degenerate many-body eigenenergy fractions for atom numbers below the critical atom number at which attraction-induced collapse occurs. The sensitivity to state pair relative parity and our variational width analyses indicate, however, that one and two single-particle state models are ultimately insufficient for these systems. Mechanism-independent, such bright short coherence length matter-wave sources, analogous to superluminescent diodes, could prove useful in actualizing portable atom-based sensors.
Description
| Type of resource | text |
|---|---|
| Form | electronic; electronic resource; remote |
| Extent | 1 online resource. |
| Publication date | 2010 |
| Issuance | monographic |
| Language | English |
Creators/Contributors
| Associated with | Cizek, Nicholas Charles |
|---|---|
| Associated with | Stanford University, Department of Applied Physics |
| Primary advisor | Kasevich, Mark A |
| Thesis advisor | Kasevich, Mark A |
| Thesis advisor | Goldhaber-Gordon, David, 1972- |
| Thesis advisor | Mabuchi, Hideo |
| Advisor | Goldhaber-Gordon, David, 1972- |
| Advisor | Mabuchi, Hideo |
Subjects
| Genre | Theses |
|---|
Bibliographic information
| Statement of responsibility | Nicholas Charles Cizek. |
|---|---|
| Note | Submitted to the Department of Applied Physics. |
| Thesis | Ph.D. Stanford University 2010 |
| Location | electronic resource |
Access conditions
- Copyright
- © 2010 by Nicholas Charles Cizek
- License
- This work is licensed under a Creative Commons Attribution Non Commercial 3.0 Unported license (CC BY-NC).
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