论文标题
BCS-BEC在准二维费米超级流体中的交叉
BCS-BEC crossover in a quasi-two-dimensional Fermi superfluid
论文作者
论文摘要
我们研究了超低效费原子的准二维量子气中的bardeen-cooper-shrieffer（BCS）制度到Bose-Einstein-Condemention（BEC）制度的交叉。在高斯对波动理论中，使用有效的二维哈密顿量在原子和衣服分子之间进行了重新归一化的相互作用，我们研究了费米超流量如何受到零温度在较广泛的交叉范围内的零温度下降的影响。我们观察到，无论尺寸如何，阶参数和配对大小与BCS侧的化学潜力显示了普遍的关系。但是，这种普遍的依赖性随着相互作用强度的提高而分解了BEC极限。该结果揭示了降低性降低对配对物理学的显着影响，这也可以在戈德石模式的声速和凸参数中观察到。我们将结果与$ {}^{6} $ li原子气和分层氮化物lixzrncl的最新实验进行了比较，并找到了良好的协议。
We study the crossover from the Bardeen-Cooper-Shrieffer (BCS) regime to the Bose-Einstein-condensation (BEC) regime in a quasi-two-dimensional quantum gas of ultracold fermionic atoms. Using an effective two-dimensional Hamiltonian with renormalized interactions between atoms and dressed molecules within a Gaussian pair fluctuation theory, we investigate how Fermi superfluidity is affected by reduced dimensionality at zero temperature in a wide range of crossover. We observe that the order parameter and pair size show universal relations with the chemical potential on the BCS side, irrespective of dimensionality. However, such universal dependences break down towards the BEC limit with increasing interaction strength. This results reveal the notable effect of reduced dimenionality on pairing physics, which can also be observed in the sound velocity and convexity parameter of the Goldstone mode. We compare our results with the latest experiments in both ${}^{6}$Li atomic gases and layered nitrides LixZrNCl and find good agreements.
