Wu Ying-Hai, Wang Lei, Tu Hong-Hao
School of Physics and Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan 430074, China.
Beijing National Lab for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
Phys Rev Lett. 2020 Jun 19;124(24):246401. doi: 10.1103/PhysRevLett.124.246401.
Tensor network states and parton wave functions are two pivotal methods for studying quantum many-body systems. This work connects these two subjects as we demonstrate that a variety of parton wave functions, such as projected Fermi sea and projected fermionic or bosonic paired states, can be represented exactly as tensor networks. The results can be compressed into matrix product states with moderate bond dimensions so various physical quantities can be computed efficiently. For the projected Fermi sea, we develop an excellent compression scheme with high fidelity using maximally localized Wannier orbitals. Numerical calculations on two parton wave functions demonstrate that our method exceeds commonly adopted Monte Carlo methods in some aspects. It produces energy and correlation function with very high accuracy that is difficult to achieve using Monte Carlo method. The entanglement measures that were almost impossible to compute before can also be obtained easily using our method.
张量网络态和部分子波函数是研究量子多体系统的两种关键方法。这项工作将这两个主题联系起来,因为我们证明了各种部分子波函数,如投影费米海以及投影费米子或玻色子配对态,可以精确地表示为张量网络。结果可以压缩成具有适度键维度的矩阵乘积态,从而可以有效地计算各种物理量。对于投影费米海,我们使用最大局域化的万尼尔轨道开发了一种具有高保真度的出色压缩方案。对两个部分子波函数的数值计算表明,我们的方法在某些方面超过了常用的蒙特卡罗方法。它能以非常高的精度产生能量和关联函数,这是使用蒙特卡罗方法难以实现的。以前几乎无法计算的纠缠度量,使用我们的方法也可以轻松获得。