Complex quantum networks as structured environments: engineering and probing

Nokkala, Johannes; Galve, Fernando; Zambrini, Roberta; Maniscalco, Sabrina; Piilo, Jyrki

doi:10.1038/srep26861

Cited by 57 publications

(66 citation statements)

References 316 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In perspective, it would be interesting to further deepen the investigation of the link between the occurrence of energy backflow and of memory effects in the reduced dynamics by relying on other suitable witnesses of non-Markovianity such as [38,41] and more structured thermal environments such as those described by sub-or super-Ohmic spectral densities [42] or such as complex oscillator networks [43].…”

Section: Discussionmentioning

confidence: 99%

Energy backflow in strongly coupled non-Markovian continuous-variable systems

et al. 2016

View full text Add to dashboard Cite

By employing the full counting statistics formalism, we characterize the first moment of energy that is exchanged during a generally non-Markovian evolution in non-driven continuous variables systems. In particular, we focus on the evaluation of the energy flowing back from the environment into the open quantum system. We apply these results to the quantum Brownian motion, where these quantities are calculated both analytically, under the weak coupling assumption, and numerically also in the strong coupling regime. Finally, we characterize the non-Markovianity of the reduced dynamics through a recently introduced witness based on the so-called Gaussian interferometric power and we discuss its relationship with the energy backflow measure.

show abstract

Section: Discussionmentioning

confidence: 99%

Energy backflow in strongly coupled non-Markovian continuous-variable systems

et al. 2016

View full text Add to dashboard Cite

show abstract

“…We give a positive answer for this question by combining earlier theoretical work on complex networks of interacting harmonic oscillators [32,34] with recent experimental advances in creating multipartite entangled states in a multimode optical system [35]. Interacting optical modes represent an interesting option because they are highly resilient to noise, highly controllable with classical instruments and efficiently detectable.…”

Section: Introductionmentioning

confidence: 99%

“…We can control the number of nodes in the network and in principle any network-whether complex or not-can be created from a given set of nodes. Moreover, the system allows to simulate quantum dynamics within the network by mapping the dynamical results of [34] for optimized experimental parameters of the optical multimode set-up. It is also important to note that each node of the network can be individually addressed which opens significant possibilities to probe the global properties of the network by detecting the local properties, as proposed in [34,41].…”

Section: Introductionmentioning

confidence: 99%

Reconfigurable optical implementation of quantum complex networks

et al. 2018

View full text Add to dashboard Cite

Network theory has played a dominant role in understanding the structure of complex systems and their dynamics. Recently, quantum complex networks, i.e.collections of quantum systems arranged in a non-regular topology, have been theoretically explored leading to significant progress in a multitude of diverse contexts including, e.g., quantum transport, open quantum systems, quantum communication, extreme violation of local realism, and quantum gravity theories. Despite important progress in several quantum platforms, the implementation of complex networks with arbitrary topology in quantum experiments is still a demanding task, especially if we require both a significant size of the network and the capability of generating arbitrary topology-from regular to any kind of non-trivial structure-in a single setup. Here we propose an all optical and reconfigurable implementation of quantum complex networks. The experimental proposal is based on optical frequency combs, parametric processes, pulse shaping and multimode measurements allowing the arbitrary control of the number of the nodes (optical modes) and topology of the links (interactions between the modes) within the network. Moreover, we also show how to simulate quantum dynamics within the network combined with the ability to address its individual nodes. To demonstrate the versatility of these features, we discuss the implementation of two recently proposed probing techniques for quantum complex networks and structured environments.

show abstract

“…It can be shown [41] that, provided the coupling to the network k is weak and the network is in a thermal state, the system excitation number is well approximated by the expression n(t) = exp(−Γt) n(0) + n(ω S )(1 − exp(−Γt)), where Γ = J(ω S )/ω S and n(ω S ) = (exp(ω S /T ) − 1) −1 , or the thermal average boson number at system frequency ω S . The value of the spectral density at system frequency is then approximated by 12) where ∆n(t) = n(ω S ) − n(t) .…”

Section: The Spectral Densitymentioning

confidence: 99%

Non-Markovianity over Ensemble Averages in Quantum Complex Networks

Nokkala

Maniscalco

Piilo

2017

Open Syst. Inf. Dyn.

Self Cite

View full text Add to dashboard Cite

Abstract. We consider bosonic quantum complex networks as structured finite environments for a quantum harmonic oscillator and investigate the interplay between the network structure and its spectral density, excitation transport properties and non-Markovianity. After a review of the formalism used, we demonstrate how even small changes to the network structure can have a large impact on the transport of excitations. We then consider the non-Markovianity over ensemble averages of several different types of random networks of identical oscillators and uniform coupling strength. Our results show that increasing the number of interactions in the network tends to suppress the average non-Markovianity. This suggests that tree networks are the random networks optimizing this quantity.

show abstract

Complex quantum networks as structured environments: engineering and probing

Cited by 57 publications

References 316 publications

Energy backflow in strongly coupled non-Markovian continuous-variable systems

Energy backflow in strongly coupled non-Markovian continuous-variable systems

Reconfigurable optical implementation of quantum complex networks

Non-Markovianity over Ensemble Averages in Quantum Complex Networks

Contact Info

Product

Resources

About