Non-dispersive optics using storage of light

We demonstrate the non-dispersive deflection of an optical beam in a Stern-Gerlach magnetic field. An optical pulse is initially stored as a spin-wave coherence in thermal rubidium vapour. An inhomogeneous magnetic field imprints a phase gradient onto the spin wave, which upon reacceleration of the optical pulse leads to an angular deflection of the retrieved beam. We show that the obtained beam deflection is non-dispersive, i.e. its magnitude is independent of the incident optical frequency. Compared to a Stern-Gerlach experiment carried out with propagating light under the conditions of electromagnetically induced transparency, the estimated suppression of the chromatic aberration reaches 10 orders of magnitude.Comment: 11 pages, 4 figures, accepted for publication in Physical Review

Alcoa Steamship Co. v. M/V Nordic Regent: Narrowing the Scope of Inquiry in Forum Non Conveniens

Increases in the amount and complexity of international trade and changes in jurisdictional rules over the last thirty years have often resulted in American courts serving as forums for suits involving non-residents. Very often these suits are the result of transactions that have occurred abroad and may be governed by foreign law as well. Obvious difficulties confront a party compelled to defend in a foreign court. Problems such as unfamiliarity with the language or legal process, unavailability of witnesses, or expenses incurred in bringing evidence from another country have led foreign defendants to seek dismissal of suits on the grounds of forum non conveniens

Shear Thickening and Scaling of the Elastic Modulus in a Fractal Colloidal System with Attractive Interactions

Dilute oil dispersions of fractal carbon black particles with attractive Van der Waals interactions display continuous shear thickening followed by shear thinning at high shear rates. The shear thickening transition occurs at $\dot\gamma_{c}\approx 10^{2}-10^{3}s^{-1}$ and is driven by hydrodynamic breakup of clusters. Pre-shearing dispersions at shear rates $\dot\gamma>\dot\gamma_{c}$ produces enhanced-modulus gels where $G' \sim \sigma_{pre-shear}^{1.5-2}$ and is directly proportional to the residual stress in the gel measured at a fixed sample age. The observed data can be accounted for using a simple scaling model for the breakup of fractal clusters under shear stress.Comment: 5 pages, 5 figures; v2: treating low shear rate date separately; edited title; reworked figure

Local Compressibility Measurements of Correlated States in Suspended Bilayer Graphene

Bilayer graphene has attracted considerable interest due to the important role played by many-body effects, particularly at low energies. Here we report local compressibility measurements of a suspended graphene bilayer. We find that the energy gaps at filling factors v = 4 do not vanish at low fields, but instead merge into an incompressible region near the charge neutrality point at zero electric and magnetic field. These results indicate the existence of a zero-field ordered state and are consistent with the formation of either an anomalous quantum Hall state or a nematic phase with broken rotational symmetry. At higher fields, we measure the intrinsic energy gaps of broken-symmetry states at v = 0, 1 and 2, and find that they scale linearly with magnetic field, yet another manifestation of the strong Coulomb interactions in bilayer graphene.Comment: 9 pages, including 4 figures and supplementary material

Transconductance fluctuations as a probe for interaction induced quantum Hall states in graphene

Transport measurements normally provide a macroscopic, averaged view of the sample, so that disorder prevents the observation of fragile interaction induced states. Here, we demonstrate that transconductance fluctuations in a graphene field effect transistor reflect charge localization phenomena on the nanometer scale due to the formation of a dot network which forms near incompressible quantum states. These fluctuations give access to fragile broken-symmetry and fractional quantum Hall states even though these states remain hidden in conventional magnetotransport quantities.Comment: 6 pages, 3 figure

Forming Maximally Diverse Workgroups: An Empirical Study

This work addresses two related important themes in business and business schools today: expanding diversity in the workplace and the increasing reliance on teams as an organizational structure. The paper describes an approach for creating student work groups where the objective is to maximize within group diversity based upon multiple criteria. This approach is an extension of a heuristic-based multiple-criteria decision support system (MCADSS) developed in earlier work (Weitz and Jelassi [1992]); that system was successfully implemented, and is currently in use, at the European Institute of Business Administration (INSEAD) in Fontainebleau, France. The heuristic has been modified here to incorporate a different set of criteria, and to allow for students placing out of core courses. This paper discusses the modified system, its implementation at the Stern School of Business at New York University (NYU), and an empirical experiment evaluating the performance of the system

SOLVING MULTI-CRITERIA ALLOCATION PROBLEMS: A DECISION SUPPORT SYSTEM APPROACH

MCADSS is a multi-criteria allocation decision support system for assisting in the task of partitioning a set of individuals into groups. Based upon multiple criteria, MCADSSâs goal is to maximize the diversity of members within groups, while minimizing the average differences between groups. (The project may be viewed from several perspectives: as a multi-criteria decision making problem, as a "reverse" clustering problem, or as a personnel assignment problem). The system is currently being used to allocate MBA students into sections and study teams at INSEAD, a leading European business school. This paper describes the rationale for MCADSS, design criteria, system methodology, and application results. It also suggests how the approach outlined here might be used for further applications.Information Systems Working Papers Serie