Environment-assisted quantum transport in a 10-qubit network

TL;DR

This study demonstrates how engineered noise can enhance energy transport in a quantum spin network, revealing a crossover from localization to efficient transport and the role of non-Markovian noise in maintaining quantum coherences.

Contribution

The paper experimentally investigates environment-assisted quantum transport in a scalable 10-qubit ion chain, highlighting the effects of static disorder and non-Markovian noise on transport efficiency.

Findings

Transport transitions from localization to ENAQT with increasing noise

Diffusive transport dominates where ENAQT is optimal

Non-Markovian noise prolongs quantum coherences

Abstract

The way in which energy is transported through an interacting system governs fundamental properties in many areas of physics, chemistry, and biology. Remarkably, environmental noise can enhance the transport, an effect known as environment-assisted quantum transport (ENAQT). In this paper, we study ENAQT in a network of coupled spins subject to engineered static disorder and temporally varying dephasing noise. The interacting spin network is realized in a chain of trapped atomic ions and energy transport is represented by the transfer of electronic excitation between ions. With increasing noise strength, we observe a crossover from coherent dynamics and Anderson localization to ENAQT and finally a suppression of transport due to the quantum Zeno effect. We found that in the regime where ENAQT is most effective the transport is mainly diffusive, displaying coherences only at very short times. Further, we show that dephasing characterized by non-Markovian noise can maintain coherences longer than white noise dephasing, with a strong influence of the spectral structure on the transport effciency. Our approach represents a controlled and scalable way to investigate quantum transport in many-body networks under static disorder and dynamic noise.