3,141 research outputs found

    Broadband quadrature-squeezed vacuum and nonclassical photon number correlations from a nanophotonic device

    Full text link
    We report the first demonstrations of both quadrature squeezed vacuum and photon number difference squeezing generated in an integrated nanophotonic device. Squeezed light is generated via strongly driven spontaneous four-wave mixing below threshold in silicon nitride microring resonators. The generated light is characterized with both homodyne detection and direct measurements of photon statistics using photon number-resolving transition edge sensors. We measure 1.0(1)1.0(1)~dB of broadband quadrature squeezing (4{\sim}4~dB inferred on-chip) and 1.5(3)1.5(3)~dB of photon number difference squeezing (7{\sim}7~dB inferred on-chip). Nearly-single temporal mode operation is achieved, with raw unheralded second-order correlations g(2)g^{(2)} as high as 1.87(1)1.87(1) measured (1.9{\sim}1.9~when corrected for noise). Multi-photon events of over 10 photons are directly detected with rates exceeding any previous quantum optical demonstration using integrated nanophotonics. These results will have an enabling impact on scaling continuous variable quantum technology.Comment: Significant improvements and updates to photon number squeezing results and discussions, including results on single temporal mode operatio

    Genetic analysis of peripheral nerve conduction velocity in twins

    Get PDF
    We studied variation in peripheral nerve conduction velocity (PNCV) and intelligence in a group of 16-year-old Dutch twins. It has been suggested that both brain nerve conduction velocity and PNCV are positively correlated with intelligence (Reed, 1984) and that heritable differences in NCV may explain part of the well established heritability of intelligence. The Standard Progressive Matrices test was administered to 210 twin pairs to obtain IQ scores. Median nerve PNCV was determined in a subgroup of 156 pairs. Genetic analyses showed a heritability of 0.65 for Raven IQ score and 0.77 for PNCV. However, there was no significant phenotypic correlation between IQ score and PNCV. © 1995 Plenum Publishing Corporation

    Tests of Lorentz violation in muon antineutrino to electron antineutrino oscillations

    Get PDF
    A recently developed Standard-Model Extension (SME) formalism for neutrino oscillations that includes Lorentz and CPT violation is used to analyze the sidereal time variation of the neutrino event excess measured by the Liquid Scintillator Neutrino Detector (LSND) experiment. The LSND experiment, performed at Los Alamos National Laboratory, observed an excess, consistent with neutrino oscillations, of νˉe{\bar\nu}_e in a beam of νˉμ{\bar\nu}_\mu. It is determined that the LSND oscillation signal is consistent with no sidereal variation. However, there are several combinations of SME coefficients that describe the LSND data; both with and without sidereal variations. The scale of Lorentz and CPT violation extracted from the LSND data is of order 101910^{-19} GeV for the SME coefficients aLa_L and E×cLE \times c_L. This solution for Lorentz and CPT violating neutrino oscillations may be tested by other short baseline neutrino oscillation experiments, such as the MiniBooNE experiment.Comment: 10 pages, 10 figures, 2 tables, uses revtex4 replaced with version to be published in Physical Review D, 11 pages, 11 figures, 2 tables, uses revtex

    Deep electronic states in ion-implanted Si

    Get PDF
    In this paper we present an overview of the deep states present after ion-implantation by various species into n-type silicon, measured by Deep Level Transient Spectroscopy (DLTS) and high resolution Laplace DLTS (LDLTS). Both point and small extended defects are found, prior to any anneal, which can therefore be the precursors to more detrimental defects such as end of range loops. We show that the ion mass is linked to the concentrations of defects that are observed, and the presence of small interstitial clusters directly after ion implantation is established by comparing their behaviour with that of electrically active stacking faults. Finally, future applications of the LDLTS technique to ion-implanted regions in Si-based devices are outlined.</p

    Search for π0νμνˉμ\pi^0 \to \nu_{\mu}\bar\nu_{\mu} Decay in LSND

    Get PDF
    We observe a net beam-excess of 8.7±6.38.7 \pm 6.3 (stat) ±2.4\pm 2.4 (syst) events, above 160 MeV, resulting from the charged-current reaction of νμ\nu_{\mu} and/or νˉμ\bar\nu_{\mu} on C and H in the LSND detector. No beam related muon background is expected in this energy regime. Within an analysis framework of π0νμνˉμ\pi^0 \to \nu_{\mu}\bar\nu_{\mu}, we set a direct upper limit for this branching ratio of Γ(π0νμνˉμ)/Γ(π0all)<1.6×106\Gamma(\pi^0 \to \nu_\mu \bar\nu_\mu) / \Gamma(\pi^0 \to all) < 1.6 \times 10^{-6} at 90% confidence level.Comment: 4 pages, 4 figure

    Ursinus College Alumni Journal, March 1956

    Get PDF
    President\u27s page • Sigma Rho scholarship fund grows • Three Ursinus alumni honored at Founders\u27 Day ceremony • 1000memorialdonationfromUrsinusWoman2˘7sClubFordFoundationgives1000 memorial donation from Ursinus Woman\u27s Club • Ford Foundation gives 191,400 to Ursinus College • Enrollment increases in Evening School • Notes from the Dean\u27s office • Ursinus presentation of Messiah recorded • From the Office of Admissions • Faculty corner • Philadelphia alumni to meet at Casa Conti • Plan now to return Alumni Day, June 2 • Spring banquet planned by Lehigh Valley • May 2nd, date for New York alumni • South Jersey alumni plan dinner-dance • Woman\u27s Club plans spring activities • Booster committee holds banquet for athletes • Ditter, Warden, Tredinnick, Assistant District Attorneys • Alumni invited to Varsity Club dinner • Dr. Gilbert Bayne \u2743 speaks to science societies • Isaac Norris of Norristown, PA • Alumni elections • Schoolmen\u27s Week teachers luncheon • Washington area alumni reorganize • Report of the loyalty fund campaign • Sports review: Football season 1955; Dave Burger named to All-American soccer team; Soccer season 1955; Wrestling; 1955 alumnae hockey; Heller and Dawkins excel in women\u27s hockey • News about ourselves • Births • Weddings • Necrologyhttps://digitalcommons.ursinus.edu/alumnijournal/1055/thumbnail.jp

    Interactions between vaccinia virus and sensitized macrophages in vitro

    Get PDF
    The action of peritoneal exudate cells (PEC) from normal and vaccinia virus infected mice on infectious vaccinia virus particles was investigatedin vitro. PEC from immune mice showed a significantly higher infectivity titre reduction (virus clearance, VC) than normal cells. This effect could be clearly attributed to the macrophage. Vaccinia virus multiplied in PEC from normal animals while there was no virus propagation in cells from immunized mice. The release of adsorbed or engulfed virus was reduced significantly in PEC from immunized animals. Anti-vaccinia-antibodies seem to activate normal macrophages to increased virus clearance. This stimulating effect was demonstrable only in the IgG fraction of the antiserum. The activity of macrophages from mice injected three times over a period of 14 days with vaccinia virus could be entirely blocked with anti-mouse-IgG, while PEC from mice injected one time six days previously were not inhibited

    Robotic ubiquitous cognitive ecology for smart homes

    Get PDF
    Robotic ecologies are networks of heterogeneous robotic devices pervasively embedded in everyday environments, where they cooperate to perform complex tasks. While their potential makes them increasingly popular, one fundamental problem is how to make them both autonomous and adaptive, so as to reduce the amount of preparation, pre-programming and human supervision that they require in real world applications. The project RUBICON develops learning solutions which yield cheaper, adaptive and efficient coordination of robotic ecologies. The approach we pursue builds upon a unique combination of methods from cognitive robotics, machine learning, planning and agent- based control, and wireless sensor networks. This paper illustrates the innovations advanced by RUBICON in each of these fronts before describing how the resulting techniques have been integrated and applied to a smart home scenario. The resulting system is able to provide useful services and pro-actively assist the users in their activities. RUBICON learns through an incremental and progressive approach driven by the feed- back received from its own activities and from the user, while also self-organizing the manner in which it uses available sensors, actuators and other functional components in the process. This paper summarises some of the lessons learned by adopting such an approach and outlines promising directions for future work

    Measurements of Charged Current Reactions of νe\nu_e on 12C^{12}C

    Get PDF
    Charged Current reactions of νe\nu_e on 12C^{12}C have been studied using a μ+\mu^+ decay-at-rest νe\nu_e beam at the Los Alamos Neutron Science Center. The cross section for the exclusive reaction 12C(νe,e)12Ng.s.^{12}C(\nu_e,e^-)^{12}N_{g.s.} was measured to be (8.9±0.3±0.9)×1042(8.9\pm0.3\pm0.9)\times10^{-42} cm2^2. The observed energy dependence of the cross section and angular distribution of the outgoing electron agree well with theoretical expectations. Measurements are also presented for inclusive transitions to 12N^{12}N excited states, 12C(νe,e)12N^{12}C(\nu_e,e^-)^{12}N^* and compared with theoretical expectations. The measured cross section, (4.3±0.4±0.6)×1042(4.3\pm0.4\pm0.6)\times10^{-42} cm2^2, is somewhat lower than previous measurements and than a continuum random phase approximation calculation. It is in better agreement with a recent shell model calculation.Comment: 34 pages, 18 figures, accepted to PRC, replaced with the accepted on

    \u201cGive, but Give until It Hurts\u201d: The Modulatory Role of Trait Emotional Intelligence on the Motivation to Help

    Get PDF
    Two studies investigated the effect of trait Emotional Intelligence (trait EI) on people\u2019s moti- vation to help. In Study 1, we developed a new computer-based paradigm that tested partic- ipants\u2019 motivation to help by measuring their performance on a task in which they could gain a hypothetical amount of money to help children in need. Crucially, we manipulated partici- pants\u2019 perceived efficacy by informing them that they had been either able to save the chil- dren (positive feedback) or unable to save the children (negative feedback). We measured trait EI using the Trait Emotional Intelligence Questionnaire\u2013Short Form (TEIQue-SF) and assessed participants\u2019 affective reactions during the experiment using the PANAS-X. Results showed that high and low trait EI participants performed differently after the presen- tation of feedback on their ineffectiveness in helping others in need. Both groups showed increasing negative affective states during the experiment when the feedback was negative; however, high trait EI participants better managed their affective reactions, modulating the impact of their emotions on performance and maintaining a high level of motivation to help. In Study 2, we used a similar computerized task and tested a control situation to explore the effect of trait EI on participants\u2019 behavior when facing failure or success in a scenario unre- lated to helping others in need. No effect of feedback emerged on participants\u2019 emotional states in the second study. Taken together our results show that trait EI influences the impact of success and failure on behavior only in affect-rich situation like those in which people are asked to help others in need
    corecore