Classically Emulated Digital Quantum Simulation of the Schwinger Model with Topological Term via Adiabatic State Preparation

Understand

We perform a digital quantum simulation of a gauge theory with a topological term in Minkowski spacetime, which is practically inaccessible by standard lattice Monte Carlo simulations.

• We focus on $1+1$ dimensional quantum electrodynamics with the $\theta$-term known as the Schwinger model.
• We construct the true vacuum state of a lattice Schwinger model using adiabatic state preparation which, in turn, allows us to compute an expectation value of the fermion mass operator with respect to the vacuum.
• Upon taking a continuum limit we find that our result in massless case agrees with the known exact result.