| DC 欄位 |
值 |
語言 |
| DC.contributor | 物理學系 | zh_TW |
| DC.creator | 廖冠博 | zh_TW |
| DC.creator | Guan-Bo Liao | en_US |
| dc.date.accessioned | 2017-9-25T07:39:07Z | |
| dc.date.available | 2017-9-25T07:39:07Z | |
| dc.date.issued | 2017 | |
| dc.identifier.uri | http://ir.lib.ncu.edu.tw:88/thesis/view_etd.asp?URN=100282005 | |
| dc.contributor.department | 物理學系 | zh_TW |
| DC.description | 國立中央大學 | zh_TW |
| DC.description | National Central University | en_US |
| dc.description.abstract | 本實驗的目標是要實現鉀-39 原子的全光學式量子氣體，
我們透過小角度交叉重疊兩道光學陷阱(optical dipole
trap,ODT)來增加捕獲的原子數目並限縮原子在軸方向的運
動。使用這個長寬比小於 20 的複合式光學陷阱，可以穩定
補捉 1 ~ 2*106個鉀原子。然後我們使用磁費許巴赫共振技
術去控制原子間的交互作用，並測量了從 20 G 至 560 G 之
間的所有譜線，我們發現許多譜線在理論工作的文獻中有發
表，但目前沒有任何的實驗發表記錄，我們藉由費許巴赫共
振技術的幫助將鉀原子團的溫度降至 10 μk 以下時發現，S
波散射長度與二體彈性碰撞截面積被有效放大，藉由費許巴
赫共振的幫助，通過強制蒸發冷卻，最佳相空間密度提高到
7 *10-3。 | zh_TW |
| dc.description.abstract |
The goal of this experiment is to realize all-optical 39K Bose-Einstein Condensates (BEC). We improved the trap loading of a near-IR laser by crossing two beams at a small angle for good loading and tighter axial con?nement. With this composite trap, we can routinely trap 1 ? 2×106 cold 39K atoms and con?ne them in a potential well with a trap aspect ratio of less than 20. We then used magnetic Feshbach resonance (FR) to control the atomic interaction in the optical trap. The S-wave scattering length is greatly tuned to improve the two-body elastic collision rate in the trap. We scanned the magnetic ?eld from 20 ? 560 G and found intra-spin and inter-spin resonances. Several peaks we found were predicted by literature but not experimental reported to our knowledge. With the help of FR, the best phase space density was increased to 7×10?3 by force evaporative cooling. | en_US |
| DC.subject | 鉀-39 原子 | zh_TW |
| DC.subject | 雷射冷卻 | zh_TW |
| DC.subject | 光學陷阱 | zh_TW |
| DC.subject | 磁費許巴赫共振 | zh_TW |
| DC.title | Laser cooling and optical trapping of potassium with tunable interaction toward quantum gas production | en_US |
| dc.language.iso | en_US | en_US |
| DC.type | 博碩士論文 | zh_TW |
| DC.type | thesis | en_US |
| DC.publisher | National Central University | en_US |