Digital quantum simulation of the Schwinger model with topological term

Date

2021/02/02 11:00 – 12:00

Venue

Online (Zoom)

Speaker

Prof. Masazumi Honda ( Yukawa Institute for Theoretical Physics, Kyoto University )

Language

English

URL

Contact

khat-AT-post.kek.jp


Overview

I am going to talk about application of quantum computation to numerical simulation of quantum field theory. Specifically we implement 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 θ-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. In massive case, we find an agreement with mass perturbation theory in small mass regime and deviations in large mass regime. We also study the confinement versus screening problem in the Schwinger model. Our results imply that digital quantum simulation is already useful tool to explore non-perturbative aspects of gauge theories with real time and topological terms. This talk is based on collaborations with Bipasha Chakraborty, Etsuko Itou, Taku Izubuchi, Yuta Kikuchi, Lento Nagano, Takuya Okuda and Akio Tomiya.

Release date 2021/01/21 Updated 2024/03/12