Multipartite nonlocality is an important measure of multipartite quantum correlations. In this paper, we show that the nonlocal n -site Mermin-Klyshko operator M̂n can be exactly expressed as a matrix product operator with a bond dimension D=2 , and then the calculation of nonlocality measure S can be simplified into standard one-dimensional (1D) tensor networks. With the help of this technique, we analyze finite-temperature multipartite nonlocality in several typical 1D spin chains, including an XX model, an XXZ model, and a Kitaev model. For...
