Generalized Lanczos method for systematic optimization of tensor network states<xref rid="cpb_27_7_070501fn1" ref-type="fn">*</xref><fn id="cpb_27_7_070501fn1"> <label>*</label><p>Project supported by the National Natural Science Foundation of China (Grant Nos. 11190024 and 11474331).</p> </fn>

Generalized Lanczos method for systematic optimization of tensor network states* *

Project supported by the National Natural Science Foundation of China (Grant Nos. 11190024 and 11474331).

Huang Rui-Zhen^{1, 2}, Liao Hai-Jun¹, Liu Zhi-Yuan^{2, 3}, Xie Hai-Dong^{1, 2}, Xie Zhi-Yuan⁴, Zhao Hui-Hai^{5, 6, 7}, Chen Jing^{1, 2}, Xiang Tao^{1, 2, 8, †}

(color online) Ground-state energy and entanglement entropy for the antiferromagnetic Heisenberg model determined by the TNS-Lanczos method based on the PEPS representation on the 4 × 4 square lattice. (a) E(n) and S(n) versus n for D = 2. The dashed line is the exact ground-state energy, E_ex = −9.1892070651930. The inset shows the difference E(0) − E_ex as a function of D. (b) Relative change of the ground state energy, [E(n) − E_ex] / [E(0) − E_ex], shown as a function of n. The result of the standard Lanczos exact diagonalization (ED) method with order-2 Krylov subspace is also shown for comparison.