论文标题
从头算路径积分的蒙特卡洛模拟陷阱中的量子偶极系统的模拟：超流体，量子统计和结构特性
Ab initio Path Integral Monte Carlo Simulations of Quantum Dipole Systems in Traps: Superfluidity, Quantum Statistics, and Structural Properties
论文作者
论文摘要
我们在谐波限制中介绍了二维量子偶极系统的二维量子偶极系统的广泛\ textit {ab intio}路径积分蒙特卡洛（PIMC）模拟，同时考虑了玻色和费米统计。这使我们能够研究非经典旋转惯性，这可能导致负超流体分数在费米子[Phys。莱特牧师。 \ textbf {112}，235301（2014）]。此外，我们详细研究了此类系统的结构特征，并能够清楚地解决量子统计数据对密度曲线和相应壳结构的影响。此外，我们介绍了更先进的中心两个粒子相关函数的结果[Phys。 Rev. e \ e \ textbf {91}，043104（2015）]，它允许检测在其他可观察到的密度（如密度）中未表现出来的fermi-和Bose-System之间的差异。总体而言，我们发现，玻色粒系统甚至对偶极子偶联强度的少量值敏感，而Pauli排除原理有效地掩盖了这种弱相互作用。此外，费米子的异常超流体分数不会反映系统的结构特性，即使惯性的力矩彼此不同，该系统的结构特性也等于玻色子。最后，我们已经证明，尽管存在臭名昭著的费米昂符号问题，但量子偶极系统的费米子PIMC模拟是可行的，这为该领域的未来研究开辟了新的途径。
We present extensive \textit{ab initio} path integral Monte Carlo (PIMC) simulations of two-dimensional quantum dipole systems in a harmonic confinement, taking into account both Bose- and Fermi-statistics. This allows us to study the nonclassical rotational inertia, which can lead to a negative superfluid fraction in the case of fermions [Phys. Rev. Lett. \textbf{112}, 235301 (2014)]. Moreover, we study in detail the structural characteristics of such systems, and are able to clearly resolve the impact of quantum statistics on density profiles and the respective shell structure. Further, we present results for a more advanced center-two particle correlation function [Phys. Rev. E \textbf{91}, 043104 (2015)], which allows to detect differences between Fermi- and Bose-systems that do not manifest in other observables like the density. Overall, we find that bosonic systems sensitively react to even small values of the dipole--dipole coupling strength, whereas such a weak interaction is effectively masked for fermions by the Pauli exclusion principle. In addition, the abnormal superfluid fraction for fermions is not reflected by the structural properties of the system, which are equal to the bosonic case even though the moments of inertia diverge from each other. Lastly, we have demonstrated that fermionic PIMC simulations of quantum dipole systems are feasible despite the notorious fermion sign problem, which opens up new avenues for future investigations in this field.
