Dipartimento di Fisica, Università di Trento and CNR-INO BEC Center, I-38050 Povo, Trento, Italy.
Phys Rev Lett. 2012 Nov 16;109(20):200401. doi: 10.1103/PhysRevLett.109.200401. Epub 2012 Nov 12.
The liquid and crystal phases of a single-component Fermi gas with dipolar interactions are investigated using quantum Monte Carlo methods in two spatial dimensions and at zero temperature. The dipoles are oriented by an external field perpendicular to the plane of motion, resulting in a purely repulsive 1/r(3) interaction. In the liquid phase we calculate the equation of state as a function of the interaction strength and other relevant properties characterizing the Fermi-liquid behavior: effective mass, discontinuity at the Fermi surface, and pair correlation function. In the high density regime we calculate the equation of state of the Wigner crystal phase and the critical density of the liquid to solid quantum phase transition. Close to the freezing density we also search for the existence of a stripe phase, but such a phase is never found to be energetically favorable.
使用二维量子蒙特卡罗方法并在零温条件下研究了具有偶极相互作用的单组分费米气体的液态和晶相。偶极子由垂直于运动平面的外场取向，导致纯排斥 1/r(3)相互作用。在液相中，我们计算了作为相互作用强度和其他描述费米液体行为的相关性质的函数的状态方程：有效质量、费米面处的不连续性和对关联函数。在高密度 regime 下，我们计算了威格纳晶体相的状态方程和液相到固体量子相变的临界密度。在接近冻结密度的地方，我们还搜索了条纹相的存在，但从未发现这种相在能量上是有利的。
