Quantum routing of information using chiral quantum walks

We address routing of classical and quantum information over quantum network, and show how to exploit chirality to achieve nearly optimal and robust transport. In particular, we prove how continuous time chiral quantum walks over a minimal graph may be used to model directional transfer and routing of information over a network. At first, we show how classical information, encoded onto an excitation localized at one vertex of a simple graph, may be sent to any other chosen location with nearly unit fidelity by tuning a single phase. Then, we prove that high-fidelity transport is also possible for coherent superpositions of states, i.e. for routing of quantum information. Furthermore, we show that by tuning the phase parameter one obtains universal quantum routing, i.e. indipendent on the input state. In our scheme, chirality is governed by a single phase, and the routing probability is robust against fluctuations of this parameter. Finally, we address characterization of quantum routers and show how to exploit the self energies of the graph to achieve high precision in estimating the phase parameter.Comment: This paper has been submitted to the Jonathan P. Dowling Memorial Special Issue of AVS QUANTUM SCIENCE (https://publishing.aip.org/publications/journals/special-topics/aqs/

Analisi degli effetti idrodinamici di un drenaggio sottotelo in una discarica controllata

L’articolo sviluppa l’analisi di rischio conseguente alla presenza di un drenaggio “sottotelo”, posto inferiormente alla barriera impermeabile artificiale di una discarica controllata. Il problema è risolto mediante un modello agli elementi finiti per la soluzione del moto e del trasporto entro un mezzo poroso, in cui sono confrontati risultati per due casi antitetici di presenza e assenza del drenaggio sottotelo. L’analisi, condotta in condizioni insature e in moto transitorio, ha evidenziato che, a seguito del formarsi di un battente idraulico entro l’ammasso di rifiuti e per valori usuali di trasmissività idraulici, lo strato drenante “sottotelo” tende a saturarsi rapidamente, determinando un maggiore rischio di diffusione del percolato per la fuoriuscita accidentale o strutturale da deterioramenti nel telo posto al fondo. Alla luce dei risultati ottenuti, l’esclusione normativa di un simile presidio (D.Lgs 36/2003) è quindi improntata alla massima cautela ai fini della protezione ambientale

Formulation of the Electric Vehicle Charging and Routing Problem for a Hybrid Quantum-Classical Search Space Reduction Heuristic

Publisher Copyright: © 2023 IEEE.Combinatorial optimization problems have attracted much interest in the quantum computing community in the recent years as a potential testbed to showcase quantum advantage. In this paper, we show how to exploit multilevel carriers of quantum information - qudits - for the construction of algorithms for constrained quantum optimization. These systems have been recently introduced in the context of quantum optimization and they allow us to treat more general problems than the ones usually mapped into qubit systems. In particular, we propose a hybrid classical quantum heuristic strategy that allows us to sample constrained solutions while greatly reducing the search space of the problem, thus optimizing the use of fewer quantum resources. As an example, we focus on the Electric Vehicle Charging and Routing Problem (EVCRP). We translate the classical problem and map it into a quantum system, obtaining promising results on a toy example which shows the validity of our technique.Peer reviewe

Analysis of Outcomes in Ischemic vs Nonischemic Cardiomyopathy in Patients With Atrial Fibrillation A Report From the GARFIELD-AF Registry

IMPORTANCE Congestive heart failure (CHF) is commonly associated with nonvalvular atrial fibrillation (AF), and their combination may affect treatment strategies and outcomes