Researchers from the University of Geneva, the Hebrew University of Jerusalem, Karlsruhe Institute of Technology, and the University of Cologne have collaborated on a study that delves into the dynamics of entanglement in quantum many-body systems under steady-state transport conditions. Their work, published in the journal Physical Review Letters, explores the use of information as a key quantity related to entanglement and demonstrates how information currents can be experimentally accessed through noise measurements.
Understanding the entanglement dynamics in quantum systems is a complex challenge, particularly when trying to develop hydrodynamic equations akin to those used for charge or heat transport. The nonlocal nature of entanglement and the difficulty in identifying conservation laws make this task even more daunting. The researchers, led by Andrea Nava and Claudia Artiaco, have employed the recently developed “information lattice” framework to characterize spatially and scale-resolved information currents in nonequilibrium open quantum systems.
The study focuses on noninteracting fermion chains coupled to dissipative reservoirs, using Lindblad master equations to model the systems. By relating the information lattice to a noise lattice constructed from particle-number fluctuations, the researchers show that information is experimentally accessible via noise measurements. Local information currents can also be obtained by measuring particle currents, onsite occupations, and covariances of particle numbers and/or particle currents.
The researchers use the fermionic negativity to quantify bipartite entanglement and study transport-induced entanglement and its relation to information currents. They find that in a clean particle-hole symmetric chain, information currents are shielded from entering the information lattice. However, impurities or particle-hole asymmetry break this effect, causing information current flow and entanglement between end segments of the chain.
This research opens the door to systematic investigations of information transport and entanglement generation in driven open quantum systems far from equilibrium. The practical applications for the energy sector could include advancements in quantum energy devices, such as quantum batteries and quantum heat engines, where understanding and controlling entanglement and information transport are crucial. Additionally, the insights gained from this study could contribute to the development of more efficient and robust quantum technologies for energy storage and conversion.
Source: Physical Review Letters, “Information transport and transport-induced entanglement in open fermion chains”
This article is based on research available at arXiv.