Fig. 1: Linear response method.
From: A linear response framework for quantum simulation of bosonic and fermionic correlation functions
We establish an equivalence between the experimental measurement of a response function and an ancilla-free quantum simulation under a time dependent Hamiltonian that includes the perturbative excitation h(t)B. Following excitation, the system is evolved under \({{{{{{{{\mathcal{H}}}}}}}}}_{0}\), and A is measured. The functional derivative of A(t) = 〈A(t)〉 with respect to \(h({t}^{{\prime} })\) yields the retarded response function shown in the figure. The data shown is taken from Fig. 3.
