28,893 research outputs found

    Dynamical Screening of Atom Confined by Finite-Width Fullerene

    Full text link
    This is an investigation on the dynamical screening of an atom confined within a fullerene of finite width. The two surfaces of the fullerene lead to the presence of two surface plasmon eigenmodes. It is shown that, in the vicinity of these two eigenfrequencies, there is a large enhancement of the confined atom's photoabsorption rate.Comment: 10 pages, 4 figures correction of figure 2 and equation 1

    The Psychophysiology of Real-Time Financial Risk Processing

    Get PDF
    A longstanding controversy in economics and finance is whether financial markets are governed by rational forces or by emotional responses. We study the importance of emotion in the decisionmaking process of professional securities traders by measuring their physiological characteristics, e.g., skin conductance, blood volume pulse, etc., during live trading sessions while simultaneously capturing real-time prices from which market events can be defined. In a sample of 10 traders, we find significant correlation between electrodermal responses and transient market events, and between changes in cardiovascular variables and market volatility. We also observe differences in these correlations among the 10 traders which may be systematically related to the traders' levels of experience.

    Sub-10 nm colloidal lithography for integrated spin-photo-electronic devices

    Full text link
    Colloidal lithography [1] is how patterns are reproduced in a variety of natural systems and is used more and more as an efficient fabrication tool in bio-, opto-, and nano-technology. Nanoparticles in the colloid are made to form a mask on a given material surface, which can then be transferred via etching into nano-structures of various sizes, shapes, and patterns [2,3]. Such nanostructures can be used in biology for detecting proteins [4] and DNA [5,6], for producing artificial crystals in photonics [7,8] and GHz oscillators in spin-electronics [9-14]. Scaling of colloidal patterning down to 10-nm and below, dimensions comparable or smaller than the main relaxation lengths in the relevant materials, including metals, is expected to enable a variety of new ballistic transport and photonic devices, such as spin-flip THz lasers [15]. In this work we extend the practice of colloidal lithography to producing large-area, near-ballistic-injection, sub-10 nm point-contact arrays and demonstrate their integration in to spin-photo-electronic devices.Comment: 15 pages, 5 figure

    On the Exponential Decay of the n-point Correlation Functions and the Analyticity of the Pressure

    Full text link
    The goal of this paper is to provide estimates leading to a direct proof of the exponential decay of the n-point correlation functions for certain unbounded models of Kac type. The methods are based on estimating higher order derivatives of the solution of the Witten Laplacian equation on one forms associated with the hamiltonian of the system. We also provide a formula for the Taylor coefficients of the pressure that is suitable for a direct proof the analyticity

    Orbital Magnetic Dipole Mode in Deformed Clusters: A Fully Microscopic Analysis

    Get PDF
    The orbital M1 collective mode predicted for deformed clusters in a schematic model is studied in a self-consistent random-phase-approximation approach which fully exploits the shell structure of the clusters. The microscopic mechanism of the excitation is clarified and the close correlation with E2 mode established. The study shows that the M1 strength of the mode is fragmented over a large energy interval. In spite of that, the fraction remaining at low energy, well below the overwhelming dipole plasmon resonance, is comparable to the strength predicted in the schematic model. The importance of this result in view of future experiments is stressed.Comment: 10 pages, 3 Postscript figures, uses revte

    How can we re-define Joseph Needham's sense of a world community for the 21st century?

    Get PDF
    In the middle of World War II, my father, Kenneth Lo, accompanied Joseph Needham on a lecture tour to Colchester Co-operative Society dedicated to the support of China’s war effort and to boycotting Japanese goods. They were comrades-in-arms, soft-left socialists, inspired by the Spanish Civil War, George Orwell and WH Auden alike to take up the pen and the campaign circuit. This article is a reflection on the politics and aesthetics of research, on decentring the Eurocentric narrative of the history of science, but also on the role of poetry in the quest for a better world. Grounded in socialist, Christian and 20th-century scientific utopian belief, All under Heaven was to be One Community. Post Needham, but in the Needham spirit, I ask what shared vision drives our research

    Dead or Alive: martial arts and the forensic gaze

    Get PDF
    The contemporary worldwide addiction to the forensic-medical gaze, the power to see both the patterns of brutality inscribed on a body and the moral truths about whodunit, how and why they did it, and sometimes with whom, took a fascinating turn in Peter Chan’s (Chen Kexin 陳可辛) Chinese martial arts film Dragon (2011), hereafter referred to by its Chinese title Wuxia 武侠, ‘Martial Chivalry’. In a brilliant twenty-first century appropriation of both ancient Chinese medical traditions and the much-loved forensic detective genre, Wuxia pushes the martial arts epic in a new direction with a minute visual analysis of the anatomy and physiology of the martial arts body

    Self-consistency in the Projected Shell Model

    Full text link
    The Projected Shell Model is a shell model theory built up over a deformed BCS mean field. Ground state and excited bands in even-even nuclei are obtained through diagonalization of a pairing plus quadrupole Hamiltonian in an angular momentum projected 0-, 2-, and 4-quasiparticle basis. The residual quadrupole-quadrupole interaction strength is fixed self-consistently with the deformed mean field and the pairing constants are the same used in constructing the quasiparticle basis. Taking 160Dy^{160}Dy as an example, we calculate low-lying states and compare them with experimental data. We exhibit the effect of changing the residual interaction strengths on the spectra. It is clearly seen that there are many Jπ=0+,1+,4+J^\pi = 0^+, 1^+, 4^+ bandheads whose energies can only be reproduced using the self-consistent strengths. It is thus concluded that the Projected Shell Model is a model essentially with no free parameters.Comment: 13 pages, 10 figures, submitted to Nuclear Physics
    corecore