Speech Communication

Contains research objectives and reports on four research projects.U.S. Air Force (Electronic Systems Division) under Contract AF 19(628)-3325National Institutes of Health (Grant NB-04332-03

Speech Communication

Contains research objectives and reports on three research projects.U. S. Air Force (Electronic Systems Division) under Contract AF19(628)-5661National Institutes of Health (Grant 5 RO1 NB-04332-04

Complexes of stationary domain walls in the resonantly forced Ginsburg-Landau equation

The parametrically driven Ginsburg-Landau equation has well-known stationary solutions -- the so-called Bloch and Neel, or Ising, walls. In this paper, we construct an explicit stationary solution describing a bound state of two walls. We also demonstrate that stationary complexes of more than two walls do not exist.Comment: 10 pages, 2 figures, to appear in Physical Review

Speech Communication

Contains reports on four research projects.U. S. Air Force Cambridge Research Laboratories under Contract F19628-69-C-0044National Institutes of Health (Grant 5 RO1 NS 04332-08

Speech Communication

Contains reports on three research projects.U. S. Air Force Cambridge Research Laboratories, Office of Aerospace Research under Contract F19628-69-C-0044National Institutes of Health (Grant 2 ROl NB-04332-06

Speech Communication

Contains research objectives and summary of research.National Institutes of Health (Grant 2 RO1 NS04332-11)National Institutes of Health (Grant 5 RO1 NS04332-11)U. S. Navy Office of Naval Research (Contract ONR N00014-67-A-0204-0069

Conference on Ferrimagnetism, 11-12 October, 1954

The eighteen papers which were presented at the conference on ferrimagnetism at the U. S. Naval Ordnance Laboratory, 11-12 October 1954, are summarized. Pertinent discussions are also included

INVERSE SCATTERING TRANSFORM ANALYSIS OF STOKES-ANTI-STOKES STIMULATED RAMAN SCATTERING

Zakharov-Shabat--Ablowitz-Kaup-Newel-Segur representation for Stokes-anti-Stokes stimulated Raman scattering is proposed. Periodical waves, solitons and self-similarity solutions are derived. Transient and bright threshold solitons are discussed.Comment: 16 pages, LaTeX, no figure

Modulational instability in periodic quadratic nonlinear materials

We investigate the modulational instability of plane waves in quadratic nonlinear materials with linear and nonlinear quasi-phase-matching gratings. Exact Floquet calculations, confirmed by numerical simulations, show that the periodicity can drastically alter the gain spectrum but never completely removes the instability. The low-frequency part of the gain spectrum is accurately predicted by an averaged theory and disappears for certain gratings. The high-frequency part is related to the inherent gain of the homogeneous non-phase-matched material and is a consistent spectral feature.Comment: 4 pages, 7 figures corrected minor misprint