Jamet, F; Lindoy, L P; Rath, Y; Lenihan, C; Agarwal, A; Fontana, E; Simkovic, F; Martin, B A; Rungger, I (2025) Anderson impurity solver integrating tensor network methods with quantum computing. APL Quantum, 2 (1). 016121 ISSN 2835-0103

Preview

Text eid10315.pdf - Published Version Available under License Creative Commons Attribution Non-commercial No Derivatives. Download (5MB) | Preview

Abstract

Solving the Anderson impurity model typically involves a two-step process, where one first calculates the ground state of the Hamiltonian and then computes its dynamical properties to obtain Green’s function. Here, we propose a hybrid classical/quantum algorithm where the first step is performed using a classical computer to obtain the tensor network ground state as well as its quantum circuit representation and the second step is executed on the quantum computer to obtain Green’s function. Our algorithm exploits the efficiency of tensor networks for preparing ground states on classical computers and takes advantage of quantum processors for the evaluation of the time evolution, which can become intractable on classical computers. We demonstrate the algorithm using 24 qubits on a quantum computing emulator for SrVO3 with a multi-orbital Anderson impurity model within the dynamical mean field theory. The tensor network based ground state quantum circuit preparation algorithm can also be performed for up to 60 qubits with our available computing resources, while the state vector emulation of the quantum algorithm for time evolution is beyond what is accessible with such resources. We show that, provided that the tensor network calculation is able to accurately obtain the ground state energy, this scheme does not require a perfect reproduction of the ground state wave function on the quantum circuit to give an accurate Green’s function. This hybrid approach may lead to quantum advantage in materials simulations where the ground state can be computed classically, but where the dynamical properties cannot.

Item Type:	Article
Keywords:	Anderson impurity model, Density matrix renormalization group, Quantum state, Tensor network theory, Quantum algorithms, Quantum computing
Subjects:	Quantum Phenomena > Quantum Information Processing and Communication
Divisions:	Quantum Technologies
Identification number/DOI:	10.1063/5.0245488
Last Modified:	16 Mar 2026 15:13
URI:	https://eprintspublications.npl.co.uk/id/eprint/10315