Disorder and the Fractional Quantum Hall Effect: Activation-Energies and the Collapse of the Gap

  • Girvin S.
  • Liu K.
  • Macdonald A.
  • Platzman P.

We examine the broadening of the collective excitations of a fractional Hall state due to disorder. Because of the absence of screening at long wavelength in this regime, we believe that the broadening depends mostly on the ionized impurity contribution to the disorder potential.

Optoelectronic Materials and Processes for Communications

  • Laudise R.

Optical communications has provided a driving force for much recent research in optoelectronic materials including laser, non-linear and optical fiber materials. Present research focuses on second generation materials: very low loss non-SiO sub 2 based fibers, very long wavelength lasers including quaternary III-V solid solutions lattice matched to GaSb, (HgCd)Te ...

Detection of Clump and Interclump Gas in the Rosette Molecular Cloud Complex

  • Blitz L.
  • Stark A.

High resolution, high sensitivity CO and sup CO observations have been made of the Rosette Molecular Cloud COmplex at one beamwidth resolution. Clumpiness of the sup CO is seen everywhere in the complex.

Redox Capacity and Direct-Current Electron Conductivity in Electroactive Materials

  • Chidsey C.
  • Murray R.

The storage and transport of charge in electroactive materials are closely related. We develpo the macroscopic concepts of "redox capacity." p, and "DC electron conductivity," sigma sub e.

Front End Software for Online Database Searching. Part 2: The Marketplace

  • Hawkins D.
  • Levy L.

INTRODUCTION: Online database producers and retrieval services (databanks) are currently in a period of intense change because their traditional market, professional search intermediaries, is close to saturation. The present online information industry growth rate - such as 30% per year[1]- must be sustained for the participants to remain profitable; the ...

Markov Reliability Models of Fault Tolerant Distributed Computed Systems

  • Liron M.
  • Melamed B.
  • Yau S.

A hierachical view of fault-tolerant distributed computers is presented, viewing a distributed computing system as composed of interconnected, interacting, functional modules. Each module, modeled by a directed-state graph, is governed by internal random failure events and counteracting recovery processes, and also by coupling of external random events from other modules.

Photonic Switching Using Directional Couplers

  • Hinton H.

1. INTRODUCTION: In the past few years photonic switching has taken on several different meanings. In the most general case photonic switching refers to any system where the inputs to an interconnection network are streams of photons incoded with information and the outputs of the network are also streams of ...

Optical Guided-Wave Devices

  • Alferness R.

Introduction: Since the demonstration of the laser twenty- five years ago, the promise of very-high capacity communications via an optical carrier has stimulated wide-spread research on electro- optical devices. This promise became a virtual reality with the achievement of low-loss silica fiber, whose transmission loss is now as low as

Testing of VLSI Chips

  • Agrawal P.

VLSI circuits with device counts in excess of 100,000 and more offer an exceptional challenge in the area of testing. Also, a substantial fraction of the chip cost is derived from the testing cost. Since testing is the final stage in the design process the chips have to be tested ...

Deques with Heap Order

  • Gajewska H.
  • Tarjan R.

A deque with heap order is a deque (double-ended queue) such that each item has a real-valued key and the operation of returning an item of minimum key is allowed as well as the usual deque operations. By combining a standard deque implementation with an auxiliary heap (priority queue) it ...

Efficient Algorithms for Finding Minimum Spanning Trees in Undirected and Directed Graphs

  • Gabow H.
  • Galil Z.
  • Spencer T.
  • Tarjan R.

Recently, Fredman and Tarjan invented a new, especially effiecient form of heap (priority queue). Their data structure, the Fibonacci heap (or F-heap) suppoets arbitrary deletion in O(logn) amortized time and other heap operations in O91) amortized time.

A Field Assisted Bonding Process for Silicon Dielectric Isolation

  • Frye R.
  • Griffith J.
  • Wong Y.

We havew developed a technique for bonding together two oxidized silicon wafers, resulting in a Si/SO sub 2 /Si structure. The process consists of applying a moderate voltage between the wafers at a temperature of 1100 to 1200C. Under these conditions, 3 inch device wafers form a uniform, microscopically defect-free ...

The Oxidation of a Terbium-Iron Alloy

  • Frankenthal R.
  • Siconolfi D.
  • Vandover R.

Amorphous thin films of Tb-Fe alloys are being investigated for use as high density mass memory storage media in magneto-optic devices. Since their magnetic properties are degraded by air oxidation of the films, it is helpful to understand the kinetics and mechanism of the oxidation reaction.

How Not to Lie with Statistics: The Correct Way to Summarize Benchmark Results

  • Fleming P.
  • Wallace J.

We have seen many examples in the literature in which normalized benchmark measurements are summarized using the arithmetic mean. We show how the use of the arithmetic mean leads to mistaken conclusions, and we suggest the use of the geometric mean when it is necessary to average normalized benchmark results.

Dispersion in BeF sub 2 Glass Lightguides

  • Cohen L.
  • Fleming J.
  • Modugno S.

Propagation characteristics have been determined for a series of BeF sub 2-based glasses used in the fabrication of lightguides. The design of multimode and single-mode fiber structures for optimizing dispersion are presented.

Noncooperative Games and Nontransitive Preferences

  • Fishburn P.
  • Rosenthal R.

A proof exactly analogous to Nash's proof for the existence of equilibria in finite non-cooperative games with von Neumann-Morgenstern utilities shows that such games have Nash equilibria when preferences satisfy the weaker conditions of 'SSB utility theory'. An example illustrates the dual roles of mixed strategies in the SSB game ...

Minimizing Bumps in Linear Extensions of Ordered Sets

  • Fishburn P.
  • Gehrlein W.

A linear extension x sub 1 x sub 2 x sub 3... of a partially ordered set (X,<) has a bump whenever x sub i < x sub i+l. We examine the problem of determining linear extensions with as few bumps as possible. Heuristic algorithms for approximate bump minimization are ...

Magnetic Insulator Glasses

  • Eibschutz M.
  • Lines M.

An outline is given of the use of Mossbauer spectroscopy as a probe of the amorphous structure and magnetic coordination in magnetic insulator glasses. Using the sup 57 Fe Mossbauer resonance as an example in the context of amorphous ferric oxides and fluorides, the manner in which both paramagnetic and ...

Antireflection Coatings on Semiconductor Laser Facets Using Sputtered Lead Silicate Glass

  • Eisenstein G.
  • Stulz L.
  • Vanuitert L.

RF-sputtered lead silicate [PbO(54 m/o)-SiO sub 2(46 m/o)] films were used to antireflection coat InGaAsP laser facets. Modal reflectivities of 1-3 x 10 sup (-4) were obtained.

Electronic Excitations on Ge sub (x) Si sub (1-x)(100)(2x1)

  • Bean J.
  • Broughton J.
  • Farrell H.
  • Schaefer J.

The presence of a reconstruction of a higher order than the nominal (2X1) superstructure has been observed for the (100) surface of Ge/Si alloys at room temperature. High-resolution electron energy loss spectroscopy (HREELS) has been used to study electronic excitation on these surfaces. Transitions were observed both between the valence ...