Variational quantum eigensolver of interacting bosons with NISQ devices

Interacting boson systems are of broad interest in different fields of physics. Their simulation on classical computers is in general very challenging. The recent advances in variational-quantum-eigensolver (VQE) algorithms offer new scalable ways to investigate these systems with noisy intermediate scale quantum (NISQ) devices. In this work, we present a proof-of-principle experiment of a boson VQE algorithm implemented on Rigetti's 8Q-device. Our experiment determines the low-energy eigenspectrum of the Rabi model -- a simple boson model with interactions mediated by an atom. Our results illustrate that scalable quantum simulations of interacting boson systems using NISQ devices have a promising future.