论文标题
基质产品状态的动量分辨时间演变
Momentum-resolved time evolution with matrix product states
论文作者
论文摘要
我们引入了一种基于基于基质产品状态（MP）的方法，用于计算（准）一维自旋链的光谱函数，直接在热力学极限的动量空间中工作。我们通过使用窗口MPS的动量叠加来将动量运算符应用于MPS基态之后，模拟时间演变。我们明确地为Spin-1海森堡链展示了纠缠的生长在动量空间，甚至在两个粒子连续体内，因此我们可以达到非常准确的光谱函数，并且键相对较小。我们将方法应用于六腿缸上的无间隙XXZ链和Square-Lattice J1-J2 Heisenberg模型的光谱线路。
We introduce a method based on matrix product states (MPS) for computing spectral functions of (quasi) one-dimensional spin chains, working directly in momentum space in the thermodynamic limit. We simulate the time evolution after applying a momentum operator to an MPS ground state by working with the momentum superposition of a window MPS. We show explicitly for the spin-1 Heisenberg chain that the growth of entanglement is smaller in momentum space, even inside a two-particle continuum, such that we can attain very accurate spectral functions with relatively small bond dimension. We apply our method to compute spectral lineshapes of the gapless XXZ chain and the square-lattice J1-J2 Heisenberg model on a six-leg cylinder.
