Humeniuk Stephan, Büchler Hans Peter
Institute for Theoretical Physics III and Center for Integrated Quantum Science and Technology, University of Stuttgart, 70550 Stuttgart, Germany.
Phys Rev Lett. 2017 Dec 8;119(23):236401. doi: 10.1103/PhysRevLett.119.236401. Epub 2017 Dec 6.
We present a method for computing the full probability distribution function of quadratic observables such as particle number or magnetization for the Fermi-Hubbard model within the framework of determinantal quantum Monte Carlo calculations. Especially in cold atom experiments with single-site resolution, such a full counting statistics can be obtained from repeated projective measurements. We demonstrate that the full counting statistics can provide important information on the size of preformed pairs. Furthermore, we compute the full counting statistics of the staggered magnetization in the repulsive Hubbard model at half filling and find excellent agreement with recent experimental results. We show that current experiments are capable of probing the difference between the Hubbard model and the limiting Heisenberg model.
我们提出了一种在行列式量子蒙特卡罗计算框架内，计算费米-哈伯德模型中诸如粒子数或磁化强度等二次可观测量的全概率分布函数的方法。特别是在具有单格点分辨率的冷原子实验中，这种全计数统计可以通过重复的投影测量获得。我们证明全计数统计可以提供关于预配对尺寸的重要信息。此外，我们计算了半填充时排斥性哈伯德模型中交错磁化强度的全计数统计，并发现与最近的实验结果非常吻合。我们表明当前的实验能够探测哈伯德模型与极限海森堡模型之间的差异。
