How to evolve an infinite temperature state in a long range Hamiltonian system?
Posted: 13 May 2024, 14:35
Hi, everyone. I'm working on calculating the infinite temperature correlation function \(\langle \hat{S}_i^z(t) \hat{S}_0^z\rangle_{\beta=0}\). The point is to evolve two states \(\lvert\psi\rangle\) and \(\hat{S}_0^z\lvert\psi\rangle\) and calculate the expectation value of \(\hat{S}_i^z\). The infinite temperature state \(\lvert\psi\rangle\) is generated by "PurificationMPS.from_infiniteT" without cooling. I know that "purification.PurificationTEBD" can be used to evolve an infinite temperature state. However, I'm dealing with a long range Hamiltonian. I guess I can only evolve the infinite temperature state by TDVP method. Yet it does not work (maybe TDVP is not suitable to evolve such a state?).
For simple \(J_1-J_2\) Heisenberg model, maybe I can group two sites and employ TEBD method? Is there a general method for general long range system? Does anyone have experience on this problem?
For simple \(J_1-J_2\) Heisenberg model, maybe I can group two sites and employ TEBD method? Is there a general method for general long range system? Does anyone have experience on this problem?