Correlation functionals of infinite volume quantum spin systems

Peng Guo

Based on an established relation that relates the integrated correlation functions for a trapped system to the infinite volume scattering phase shifts through a weighted integral, we propose to extract the infinite volume scattering phase shifts through quantum simulation of the integrated correlation functions of trapped two-particle systems on quantum computers. The integrated correlation function can be computed by an ancilla-based algorithm. The proposal is demonstrated with a simple contact interaction fermion model.

M. Fannes, Bruno Nachtergaele, Reinhard F. Werner

Akihiko Matsuyama

Masao Hirokawa

In this paper, we treat a quantum harmonic oscillator in thermal equilibrium with any systems in certain classes of bosons with infinitely many degrees of freedom. We describe the following results: (i) when a canonical correlation function is given, we so reconstmct a Hamiltonian by the rotating wave approximation from it that the Hamiltonian restores it. Namely, we solve an inverse problem in the quantum field theory at finite temperature in a finite volume. (ii) Taking an infinite volume limit for the result in (i), we consider long-time behavior of the canonical correlation function in the finite volume limit.

Guo-Feng Zhang, Heng Fan, Ai-Ling Ji +3 more

Alain H. Billoire, L Giomi, Enzo Marinari

We investigate numerically the dynamical behavior of the mean field 3-spin spin glass model: we study equilibrium dynamics, and compute equilibrium time scales as a function of the system size V . We find that for increasing volumes the time scale τ increases like ln τ ∝ V . We also present an accurate study of the equilibrium static properties of the system.