论文标题
在强烈相互作用的超低费米气体中，等温可压缩性和多体分子相互作用的影响
Isothermal compressibility and effects of multi-body molecular interactions in a strongly interacting ultracold Fermi gas
论文作者
论文摘要
从理论上讲，我们在超低费米气体的正常状态下研究了等温可压缩$κ_{t} $。包括在自一致的$ t $ -matrix近似（SCTMA）的框架内，包括配对波动以及预先形成的地层，我们评估了整个BCS（bardeen-cooper-schrieffer）中这种热力学数量的温度依赖性。虽然弱耦合BCS制度中的$κ_T$由费米表面附近的费米原子支配，但发现紧密结合的库珀对分子之间的相关性在强耦合BEC策略中起着至关重要的作用。在后一个区域，除了两体分子相互作用外，三体相互作用还显示出很大的影响$κ_T$在超丝相变温度附近。我们的结果表明，超速费米气体的强耦合BEC状态将为研究Cooper Pair分子之间的多体相关性提供独特的机会。
We theoretically investigate the isothermal compressibility $κ_{T}$ in the normal state of an ultracold Fermi gas. Including pairing fluctuations, as well as preformed-pair formations, within the framework of the self-consistent $T$-matrix approximation (SCTMA), we evaluate the temperature dependence of this thermodynamic quantity over the entire BCS (Bardeen-Cooper-Schrieffer)-BEC (Bose-Einstein condensation) crossover region. While $κ_T$ in the weak-coupling BCS regime is dominated by Fermi atoms near the Fermi surface, correlations between tightly bound Cooper-pair molecules are found to play crucial roles in the strong-coupling BEC regime. In the latter region, besides a two-body molecular interaction, a three-body one is shown to sizably affect $κ_T$ near the superfluid phase transition temperature. Our results indicate that the strong-coupling BEC regime of an ultracold Fermi gas would provide a unique opportunity to study multi-body correlations between Cooper-pair molecules.
