Generation of a soliton in a gaseous Bose-EInstein condensate and its application for measuring external fields

2018 Fiscal Year Final Research Report

• Project/Area Number: 15K05229
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Atomic/Molecular/Quantum electronics
• Research Institution: University of Fukui
• Principal Investigator: Kumakura Mitsutaka 福井大学, 学術研究院工学系部門, 教授 (30324601)
• Project Period (FY): 2015-04-01 – 2019-03-31
• Keywords: 周波数安定化レーザー / レーザー波面制御 / 半導体レーザー / レーザー冷却 / Bose-Einstein凝縮

Outline of Final Research Achievements

With the goal of demonstrating our novel precision measurement method by utilizing an atomic wave soliton generated in a gaseous Bose-Einstein condensate, we developed new optical systems for generating the soliton through the stimulated Raman transition by laser beams with controlled wavefronts; a frequency-stabilized laser source, a laser wavefront control system, and so on. We originally designed a new frequency stabilization mechanism of a semiconductor laser with two interference filters, and constructed a 780 nm laser source with a narrow frequency linewidth of nearly 15 kHz and sufficient stability. The characteristics of the wavefront control system was confirmed in practice for several higher HG and LG modes. The stimulated Raman transition was also carried out preliminarily for Rb atoms in an atomic vapor cell at a normal temperature.

Free Research Field

量子エレクトロニクス

Academic Significance and Societal Importance of the Research Achievements

原子位相の変化に基づく高感度計測器としては原子干渉計が知られているが、本研究で取り組んだ原子波ソリトンを利用する方法は、原子波の非線形性を利用する従来にない手法で、一度に多数の原子を利用するため、飛躍的に高いS/Nが期待される。本研究の成果は、その実証に必要な新たな実験装置を開発したもので、学術的に大きな意義がある。また、本研究で実現した簡便なレーザー周波数安定化の手法やレーザー波面の位相制御法は、他分野の高精度光学実験においても重要な実験手法であり、工学的な面でもその意義は大きい。