| DC 欄位 |
值 |
語言 |
| DC.contributor | 物理學系 | zh_TW |
| DC.creator | 余欣鴻 | zh_TW |
| DC.creator | Hsin-Hung Yu | en_US |
| dc.date.accessioned | 2022-8-11T07:39:07Z | |
| dc.date.available | 2022-8-11T07:39:07Z | |
| dc.date.issued | 2022 | |
| dc.identifier.uri | http://ir.lib.ncu.edu.tw:88/thesis/view_etd.asp?URN=107222001 | |
| 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 | 本論文試圖為實驗室發展一種偏頻鎖頻技術，我們稱為脈衝偏頻鎖相，讓一
般的鎖模雷射透過一台光梳雷射也能間接的參考到銫原子鐘上，關鍵在於利用一台有架設自參考系統的光梳雷射作為其他無法確認其自身偏移頻率的鎖模雷射的頻率參考。
這項技術主要是用來研究Cs&Rb 混合原子的直接光梳光譜，主要研究
Cs:6S1/2→6P3/2→8S1/2 與Rb:5S1/2→5P3/2→5D5/2 之階梯式雙光子躍遷(stepwise two-photon transition)。其中Rb 譜線是BIPM 建議的頻率標準之一，這項研究有助於發展利用光梳雷射與Cs&Rb 混合原子建立光鐘的實驗技術。
過去實驗室使用的脈衝雷射需要依賴與其他單頻穩頻雷射拍頻才能得知偏移頻率，然而我們的單頻穩頻雷射無法直接給出絕對頻率。當時實驗室的學長發現Cs光譜與理論計算可以有200~300 kHz的誤差，這現像由當時已知的所有可能的誤差來源都無法完全解釋，或是缺乏直接證據。為了彌補實驗無法直接給出絕對頻率的缺陷，我使用了脈衝偏頻鎖相技術鎖定雷射，並由此雷射掃描原子譜線，再次驗證了300 kHz的誤差，並且發現原因是原子受到磁場產生的Zeeman shift。我們嘗試修正這樣的誤差，並暫時驗證脈衝偏頻鎖相用於原子光譜掃描的可靠性。
我們依過去Cs:6S1/2→8S1/2 直接雙光子躍遷的實驗經驗，認為Cs 對於雙光子躍遷對於磁場並不敏感。透過這次實驗我們發現如果是階梯式雙光子躍遷則可能對磁場非常敏感，在論文中我將由基本的原子物理解釋這樣差異。 | zh_TW |
| dc.description.abstract | This paper attempts to develop a offset-frequency locking technology for our laboratory, which we call pulse offset frequency locking technique. This technique can indirectly refer ordinary mode-locked lasers to cesium atomic clocks through an optical comb laser. The key is to use an optical comb laser with self-referencesystem as a frequency reference for other mode-locked lasers that cannot confirm their carrier-envelope offset frequency.
This technique is use to study direct frequency-comb spectroscopy of Cs&Rb atoms, mainly Cs:6S1/2→6P3/2→8S1/2and Rb:5S1/2→5P3/2→5D5/2stepwise two-photon transition. While Rb spectral line is one of the frequency standards suggested by BIPM. This research develops experimental techniques for building optical clocks using comb lasers and Cs&Rb mixed atomic cell.
In the past, mode-locked laser in our laboratory needs beat frequency with other stabilized single-frequency lasers to obtain the carrier envelope offset frequency. However, the absolute frequency of our stabilized single-frequency laser is unconfirmed. From past experiments in our laboratory, our senior member found that the Cs spectra had an error of 200~300 kHz compared with the theoretical calculation. In order to solve the defect that absolute frequency cannot be directly obtained in the experiment, I locked the mode-locked laser with pulse offset frequency locking technique, and use this laser to scan the atomic spectral lines. We confirmed the reason of 300 kHz error is Zeeman shift caused by magnetic field on atomic cell. We try to correct this error and verify the reliability of the pulse offset frequency locking technique for scanning atomic spectra.
According to experiences from Cs:6S1/2→8S1/2direct twophoton transition experiments, We think that the 6S1/2→8S1/2 two-photon transition of Cs is insensitive to magnetic fields. However, from this experiment we found that the transition may be very sensitive to magnetic fields if it is a stepped two-photon transition. In this paper I will explain the difference between the two types of two-photon transition from atomic physics. | en_US |
| DC.subject | 光梳雷射 | zh_TW |
| DC.subject | 偏頻鎖相 | zh_TW |
| DC.subject | 脈衝同步 | zh_TW |
| DC.subject | 直接光梳光譜 | zh_TW |
| DC.subject | Optical frequency comb | en_US |
| DC.subject | Offset-frequency locking | en_US |
| DC.subject | Pulse synchronization | en_US |
| DC.subject | Direct frequency-comb spectroscopy | en_US |
| DC.title | 偏頻鎖相超短脈衝雷射以實現銫及銣原子高解析直接光梳光譜 | zh_TW |
| dc.language.iso | zh-TW | zh-TW |
| DC.title | High resolution direct comb spectra of Cs & Rb atoms by offset frequency locked pulse laser | en_US |
| DC.type | 博碩士論文 | zh_TW |
| DC.type | thesis | en_US |
| DC.publisher | National Central University | en_US |