Fermionic approach to variational quantum simulation of Kitaev spin models
Li, Andy C.Y.
Perdue, Gabriel N.
Alam, M. Sohaib
Tubman, Norm M.
Is Version Of
Physics and Astronomy
We use the variational quantum eigensolver (VQE) to simulate Kitaev spin models with and without integrability breaking perturbations, focusing in particular on the honeycomb and square-octagon lattices. These models are well known for being exactly solvable in a certain parameter regime via a mapping to free fermions. We use classical simulations to explore a novel variational ansatz that takes advantage of this fermionic representation and is capable of expressing the exact ground state in the solvable limit. We also demonstrate that this ansatz can be extended beyond this limit to provide excellent accuracy when compared to other VQE approaches. In certain cases, this fermionic representation is advantageous because it reduces by a factor of two the number of qubits required to perform the simulation. We also comment on the implications of our results for simulating non-Abelian anyons on quantum computers.
This is a pre-print of the article Jahin, Ammar, Andy CY Li, Thomas Iadecola, Peter P. Orth, Gabriel N. Perdue, Alexandru Macridin, M. Sohaib Alam, and Norm M. Tubman. "Fermionic approach to variational quantum simulation of Kitaev spin models." arXiv preprint arXiv:2204.05322 (2022). https://arxiv.org/abs/2204.05322v1. Attribution 4.0 International (CC BY 4.0). Copyright 2022 The Authors. Posted with permission.