We systematically investigate the zero temperature phase diagram of bosons interacting via dipolar interactions in three dimensions in free space via path integral Monte Carlo simulations with a few hundreds of particles and periodic boundary conditions based on the worm algorithm. Upon increasing the strength of the dipolar interaction and at sufficiently high densities we find a wide region where filaments are stabilized along the direction of the external field. Most interestingly by computing the superfluid fraction we conclude that the superfluidity is anisotropic and is greatly suppressed along the orthogonal plane. Finally, we perform simulations at finite temperature confirming the stability of the filaments against thermal fluctuations and provide an estimate of the superfluid fraction in the weak coupling limit in the framework of the Landau two-fluid model.

中文翻译：

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自由空间中偶极玻色子的超流体丝

我们通过基于蠕虫算法的数百个粒子和周期性边界条件的路径积分蒙特卡罗模拟，系统地研究了玻色子在零维中通过偶极子相互作用在零维空间中的零相图，该路径积分蒙特卡罗模拟。通过增加偶极相互作用的强度并以足够高的密度，我们发现了一个宽的区域，在该区域中，细丝沿着外场的方向稳定了。最有趣的是，通过计算超流体分数，我们得出结论，超流体是各向异性的，并且沿正交平面被大大抑制了。最后，