Efficient creation of p-wave molecules in a three-dimensional optical lattice

2018 Fiscal Year Final Research Report

• Project/Area Number: 17K18752
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Research Field: Condensed matter physics and related fields
• Research Institution: Osaka University
• Principal Investigator: Mukaiyama Takashi 大阪大学, 基礎工学研究科, 教授 (70376490)
• Project Period (FY): 2017-06-30 – 2019-03-31
• Keywords: 極低温原子気体 / レーザー冷却 / 超流動 / 原子衝突 / 量子縮退 / 光格子

Outline of Final Research Achievements

Quantum gases with controllable p-wave interactions provides us with a wonderful playground to study phase transitions between superfluid phases with different symmetries. However, ultracold Fermi gases with strong p-wave interactions suffer from three-body relaxation losses. We started with the trial to understand the loss properties and experimentally identified the scaling behavior of the three-body loss in the weak interaction limit, and also the unitarity-limited behavior in the strong interaction limit. We further investigate the theoretical framework to reproduce the loss properties of the Fermi gas with strong p-wave interactions. We extend our study of the three-body loss coefficients from three-dimensional atomic gas to two-dimensional atomic gas, and investigate the possibility to improve the elastic to inelastic collision rate ratio. The result we obtained in this study paves the way toward realization of p-wave superfluid in an ultracold Fermi gas.

Free Research Field

量子エレクトロニクス

Academic Significance and Societal Importance of the Research Achievements

冷却原子系でp波超流動が実現できれば，原子間相互作用がBCS領域からBEC領域まで自在に変化させることができ，p波超流動の未踏のパラメータ領域の物性が開拓できる可能性がある。しかしフェッシュバッハ共鳴を用いて原子のp波弾性衝突を増強させると，同時に非弾性衝突による原子ロスのレートも増大してしまい，その実現は未だなされていない。本研究ではこれまであまり詳細に議論されていないp波衝突による非弾性衝突特性を３次元系から低次元系に至るまで系統的に理解することで， p波フェルミ原子対をより高い位相空間密度で生成し超流動を実現するための手法を開発することを目的としている。