Photon transport in a Bose-Hubbard chain of superconducting artificial atoms

TL;DR

This paper demonstrates non-equilibrium photon transport in a superconducting artificial atom chain, revealing many-particle coherence, energy band visualization, and the effects of disorder, with implications for quantum simulation and supremacy.

Contribution

It introduces a superconducting artificial atom chain as a platform for simulating the driven-dissipative Bose-Hubbard model with controllable disorder and demonstrates photon transport and blockade phenomena.

Findings

High-contrast visualization of energy bands using cross-Kerr interaction

Observation of transition from linear to nonlinear photon blockade regime

Disorder suppresses non-local photon transmission

Abstract

We demonstrate non-equilibrium steady-state photon transport through a chain of five coupled artificial atoms simulating the driven-dissipative Bose-Hubbard model. Using transmission spectroscopy, we show that the system retains many-particle coherence despite being coupled strongly to two open spaces. We show that system energy bands may be visualized with high contrast using cross-Kerr interaction. For vanishing disorder, we observe the transition of the system from the linear to the nonlinear regime of photon blockade in excellent agreement with the input-output theory. Finally, we show how controllable disorder introduced to the system suppresses this non-local photon transmission. We argue that proposed architecture may be applied to analog simulation of many-body Floquet dynamics with even larger arrays of artificial atoms paving an alternative way to demonstration of quantum supremacy