Stability of a Giant Connected Component in a Complex Network

We analyze the stability of the network's giant connected component under impact of adverse events, which we model through the link percolation. Specifically, we quantify the extent to which the largest connected component of a network consists of the same nodes, regardless of the specific set of deactivated links. Our results are intuitive in the case of single-layered systems: the presence of large degree nodes in a single-layered network ensures both its robustness and stability. In contrast, we find that interdependent networks that are robust to adverse events have unstable connected components. Our results bring novel insights to the design of resilient network topologies and the reinforcement of existing networked systems

Surface ligands affect photoinduced modulation of the quantum dots optical performance

ABSTRACT Changes of optical properties of the solutions of CdSe/ZnS quantum dots (QDs) covered with the trioctylphosphine oxide (TOPO) ligands under the pulsed ultraviolet (UV) laser irradiation are observed. The fluorescence quantum yield (QY) of QDs decreases by more than an order of magnitude when the radiation dose approaches 2 × 10 -15 J per particle. This process is accompanied by a blue shift of both fluorescence and the first excitonic absorption peaks. The fluorescence quenching becomes less pronounced when the overall TOPO content in the solution is increased. When ТОРО ligands are replaced with n-hexadecylamine (HDA), QY and spectral properties are not changed at the same irradiation conditions. We assume that the above changes of the optical properties are associated with photooxidation of TOPO ligands by excited QD. Such process is less probable for the HDA ligand due to its different energy structure

Energy transfer between single semiconductor quantum dots and organic dye molecules

An understanding of the mechanisms of energy transfer and conversion on the nanoscale is one of the key requirements for an implementation of highly efficient photonic nanodevices based on hybrid organic/inorganic nanomaterials. In this work we conduct steady-state and time resolved optical studies of the emission properties of an ensembles and single semiconductor quantum dots and attached organic dye molecules. We revealed that the luminescence intensity of a hybrid structure does not follow the blinking behavior of quantum dots. We also demonstrated an efficient single photon generation from single hybrid nanostructures which involves an energy transfer from donor to acceptor as main excitation source.This work was supported by the Ministry of Education and Science of the Russian Federation under grant no. 14.Y26.31.0011. Y. R. and T. H. acknowledges support from Project Fis2016.80174-P (PLASMOQUANTA) from MINECO (Ministerio de Economiá y Competitividad), Spain.Peer reviewe

Stability of a giant connected component in a complex network

The article of record as published may be found at https://doi.org/10.1103/PhysRevE.97.012309We analyze the stability of the network’s giant connected component under impact of adverse events, which we model through the link percolation. Specifically, we quantify the extent to which the largest connected component of a network consists of the same nodes, regardless of the specific set of deactivated links. Our results are intuitive in the case of single-layered systems: the presence of large degree nodes in a single-layered network ensures both its robustness and stability. In contrast, we find that interdependent networks that are robust to adverse events have unstable connected components. Our results bring novel insights to the design of resilient network topologies and the reinforcement of existing networked systems.U.S. Defense Threat Reduction AgencyNational Science Foundation (NSF)Army Research Office (ARO)Grant CCF-1212778 (NSF)Grant IIS-1741355 (NSF)Grant W911NF-16-1-0391 (ARO)Grant W911NF-17-1-0491 (ARO