Leading Order Temporal Asymptotics of the Modified Non-Linear Schrodinger Equation: Solitonless Sector

Using the matrix Riemann-Hilbert factorisation approach for non-linear evolution equations (NLEEs) integrable in the sense of the inverse scattering method, we obtain, in the solitonless sector, the leading-order asymptotics as $t$ tends to plus and minus infinity of the solution to the Cauchy initial-value problem for the modified non-linear Schrodinger equation: also obtained are analogous results for two gauge-equivalent NLEEs; in particular, the derivative non-linear Schrodinger equation.Comment: 29 pages, 5 figures, LaTeX, revised version of the original submission, to be published in Inverse Problem

Conservation Laws in Higher-Order Nonlinear Optical Effects

Conservation laws of the nonlinear Schr\"{o}dinger equation are studied in the presence of higher-order nonlinear optical effects including the third-order dispersion and the self-steepening. In a context of group theory, we derive a general expression for infinitely many conserved currents and charges of the coupled higher-order nonlinear Schr\"{o}dinger equation. The first few currents and charges are also presented explicitly. Due to the higher-order effects, conservation laws of the nonlinear Schr\"{o}dinger equation are violated in general. The differences between the types of the conserved currents for the Hirota and the Sasa-Satsuma equations imply that the higher-order terms determine the inherent types of conserved quantities for each integrable cases of the higher-order nonlinear Schr\"{o}dinger equation

Multisoliton solutions and integrability aspects of coupled nonlinear Schrodinger equations

Using Painleve singularity structure analysis, we show that coupled higher-order nonlinear Schrodinger (CHNLS) equations admit Painleve property. Using the results of Painleve analysis, we succeed in Hirota bilinearizing the CHNLS equations, one soliton and two soliton solutions are explictly obtained. Lax pairs are explictly constructed.Comment: Eight pages and six figures. Physical Review E (to be appear

Optical fiber relative humidity sensor based on a FBG with a di-ureasil coating

In this work we proposed a relative humidity (RH) sensor based on a Bragg grating written in an optical fiber, associated with a coating of organo-silica hybrid material prepared by the sol-gel method. The organo-silica-based coating has a strong adhesion to the optical fiber and its expansion is reversibly affected by the change in the RH values (15.0–95.0%) of the surrounding environment, allowing an increased sensitivity (22.2 pm/%RH) and durability due to the presence of a siliceous-based inorganic component. The developed sensor was tested in a real structure health monitoring essay, in which the RH inside two concrete blocks with different porosity values was measured over 1 year. The results demonstrated the potential of the proposed optical sensor in the monitoring of civil engineering structures

Cherenkov radiation control via self-accelerating wave-packets

Cherenkov radiation is a ubiquitous phenomenon in nature. It describes electromagnetic radiation from a charged particle moving in a medium with a uniform velocity larger than the phase velocity of light in the same medium. Such a picture is typically adopted in the investigation of traditional Cherenkov radiation as well as its counterparts in different branches of physics, including nonlinear optics, spintronics and plasmonics. In these cases, the radiation emitted spreads along a “cone”, making it impractical for most applications. Here, we employ a self-accelerating optical pump wave-packet to demonstrate controlled shaping of one type of generalized Cherenkov radiation - dispersive waves in optical fibers. We show that, by tuning the parameters of the wave-packet, the emitted waves can be judiciously compressed and focused at desired locations, paving the way to such control in any physical system

Homodyne detection for atmosphere channels

We give a systematic theoretical description of homodyne detection in the case where both the signal and the local oscillator pass through the turbulent atmosphere. Imperfect knowledge of the local-oscillator amplitude is effectively included in a noisy density operator, leading to postprocessing noise. Alternatively, we propose a technique with monitored transmission coefficient of the atmosphere, which is free of postprocessing noise.Comment: 9 pages, 5 figure

Sviluppo di tecniche di simulazione eterogenea funzionale e numerica applicate all’ingegneria di sistemi aeronautici

Questo studio illustra l’impiego del ‘Model Based Systems Engineering’ (MBSE), in cui strumenti di modellazione funzionale si integrano con modelli numerici, da tempo impiegati in progettazione, per la realizzazione di sistemi complessi. E’ analizzato un sistema antighiaccio aeronautico, sviluppato nell’ambito del progetto ‘CRYSTAL’. L’obiettivo è stato raggiunto collegando il gestore di requisiti IBM DOORS®, IBM RHAPSODY®, che opera in ambiente SysML, e SIMULINK® o DYMOLA®. L’interoperabilità è stata garantita dallo standard di connessione Functional Mock–up Interface (FMI), che ha permesso di validare il processo realizzando la cosiddetta ‘simulazione eterogenea’ di modelli funzionali e numerici integrati

Toward Global Quantum Communication: Beam Wandering Preserves Nonclassicality

Tap-proof long-distance quantum communication requires a deep understanding of the strong losses in transmission channels. Here we provide a rigorous treatment of the effects of beam wandering, one of the leading disturbances in atmospheric channels, on the quantum properties of light. From first principles we derive the probability distribution of the beam transmissivity, with the aim to completely characterize the quantum state of light. It turns out that beam wandering may preserve nonclassical effects, such as entanglement, quadrature and photon number squeezing, much better than a standard attenuating channel of the same losses.Comment: published versio

Heat-Shock Protein 90 Controls the Expression of Cell-Cycle Genes by Stabilizing Metazoan-Specific Host-Cell Factor HCFC1

Molecular chaperones such as heat-shock proteins (HSPs) help in protein folding. Their function in the cytosol has been well studied. Notably, chaperones are also present in the nucleus, a compartment where proteins enter after completing de novo folding in the cytosol, and this raises an important question about chaperone function in the nucleus. We performed a systematic analysis of the nuclear pool of heat-shock protein 90. Three orthogonal and independent analyses led us to the core functional interactome of HSP90. Computational and biochemical analyses identify host cell factor C1 (HCFC1) as a transcriptional regulator that depends on HSP90 for its stability. HSP90 was required to maintain the expression of HCFC1-targeted cell-cycle genes. The regulatory nexus between HSP90 and the HCFC1 module identified in this study sheds light on the relevance of chaperones in the transcription of cell-cycle genes. Our study also suggests a therapeutic avenue of combining chaperone and transcription inhibitors for cancer treatment