Quantum Journal Club

Universal and efficient hybrid digital-analog fermionic quantum simulator

by Haotian Wei (BNL: Condensed Matter Physics and Materials Science Department)

→ US/Eastern
Large Seminar Room (BNL Building 510 (Physics))

Large Seminar Room

BNL Building 510 (Physics)

Description

We design a universal framework for fermionic quantum hardware that runs efficient variational algorithms to simulate generic many-body systems beyond the hardware’s native interactions. Our analysis shows that one can quantum simulate the ground-state properties of a broad class of gapless target Hamiltonians of local observables in a quantum evolution time that grows polynomially with the inverse relative error  up to logarithmic corrections, and offers an exponential speedup over naïve classical algorithms such as exact diagonalization (ED). We provide numerical evidence and theoretical argument that this holds for energy density, as well as density-density and spin-spin correlations in three qualitatively distinct models – the repulsive Hubbard model; a Hubbard model augmented with nearest-neighbor attractive interactions, which introduces the phenomenon of pairing; and the Hofstadter-Hubbard model, which introduces a gauge field and fractional quantum Hall physics. This work demonstrates the usefulness of current ultracold fermionic quantum platforms for quantum simulating fermionic many-body systems beyond the models natively implemented in the hardware.

https://bnl.zoomgov.com/j/1659180989?pwd=ptKQrjBOEmGHAKtkC3TTAGNeA3lrsM.1