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We report on the effect of different aperture shapes on the power output of a very small aperture laser (VSAL) fabricated from commercial edge-emitting laser diodes and correlate the results to the layer structure and polarization of the optical field. A waveguide theory is used to explain the experimental observations. We show that the shape of the aperture has a significant effect on the VSAL output power. In particular shapes exploiting the asymmetry of the laser can achieve much higher throughput over square apertures while keeping the aperture area constant. This work also indicates the validity of analyzing near-field small apertures as cutoff waveguide structures. [ABSTRACT FROM AUTHOR]

Presents information on a study which observed a large electro-optic modulation effect in potassium titanyl phosphate waveguides fabricated under various conditions. Background of the study; Methodology of the study; Results and discussion.

Deals with a study which fabricated thin films of bismuth substituted iron garnet on silicon substrates using the pulsed laser deposition technique. Comparison between film microstructure and magnetic properties for films grown at different growth conditions and annealing procedure; Characteristics of the films heated during deposition.

Forward volume spin waves were excited in a yttrium–iron–garnet film using a microstrip delay line. Low frequency modulations in output power were captured on a digital oscilloscope for various combinations of microwave input frequency and power. Using the decrease in mutual information as a criterion, an embedding delay time was chosen for each time series. The method of false nearest neighbors was then used to calculate a minimal embedding dimension, D. Despite large changes in input frequency (4.4 GHz

Presents a study which described a hysteresis model for polycrystalline high temperature superconductors. Method of the study; Results and discussion; Conclusion.

Describes a modified ring resonator employing multielement transducers and a reduced ring circumference to excite a single resonance. Types of multibar magnetostatuc surface wave transducers; Illustration of an assembled ring resonator.

Presents a study which compared magnetostatic surface wave propagation characteristics. Method of the study; Results and discussion; Conclusion.

Studies the effect of the addition of thorium on the propagation of magnetostatic forward volume waves at X band using a differential path delay line. Growth conditions of films of thorium substituted yttrium-iron garnet; Quantity that is useful in determining the quality of a thin ferrite film for propagation of magnetostatic waves; Conclusion.

Provides information on a study that reported the use of longitudinal magnetic field variations to suppress magnetostatic backward volume wave end reflections in an yttrium-iron-garnet thin film. Methodology of the study; Results and discussion on the study.

Deals with a study which examined the variations of auto-oscillation (AO) frequency in a yttrium-iron-garnet film. Parabolic dependence of the square of the frequency of auto-oscillations on microwave signal amplitudes; Measurement of ferromagnetic resonance; Observations on the AO frequencies.

Deals with the improvement of ferromagnetic resonance linewidth in bismuth-substituted lutetium iron garnet thin films for the magnetostatic wave-optical-mode interaction. Film growth; Description of the optical properties of the films; Background on ferromagnetic resonance.

Focuses on a study which investigated the effect of the incorporation of sodium into bismuth-doped lutetium iron garnet lattice on the magnetic and magneto-optical properties of the lattice. Theoretical background of the study; Experimental procedures; Results and discussion.

An active circuit is described that exhibits the equivalent reactance of a negative inductor. In contrast with previous techniques based on negative impedance converters, the negative inductance is produced by generating an opposing time-varying magnetic flux. The new circuit also enables the inductance to be electronically varied between negative and positive values, can enhance the Q, and defaults to a conventional positive inductor in the event of active component failure. The performance of a prototype with an inductance of -0:344mH and operating over the frequency range 1-40 kHz is described. [ABSTRACT FROM AUTHOR]

A magnetic amplifying magnetooptical system (MAMMOS) model was created which calculates the size of the expanded domains in the readout layer by computing the forces on the domain wall. Using the model, the ratio of nucleation coercivity to domain wall motion coercivity, Hc•n/Hc•m, was found to be an important factor governing the final expanded domain size in MAMMOS. Simulation results indicated that Hc•n/Hc•m > 5 is needed for a good readout signal. Experiments measuring the nucleation coercivity in localized areas on a MAMMOS readout layer agree with the modeling results. In the experiments, a wafer was patterned with islands of magnetic material and the switching behavior was measured. For a MAMMOS film, the ratio of Hc•n/Hc•m was measured to be 13 on average in a 400 μm² area. [ABSTRACT FROM AUTHOR]

Optical field confinement in a ridge waveguide nanostructure (“C” aperture) designed for ultrahigh-density recording was observed using an apertureless near-field scanning optical microscope. The aperture was fabricated on a commercial edge-emitting semiconductor laser as the light source. High-contrast near-field images at both 1× and 2× lock-in detection frequencies were obtained. The emission patterns are in agreement with theoretical simulation of such structures. A 90 nm×70 nm full width half maximum spot size was measured and is comparable to the ridge width of the aperture. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We have studied the structure present at small fields (<50 Oe) in the magnetic hysteresis of polycrystalline samples of YBa2Cu3O7-x and ErBa2Cu3O7-x. This structure is absent from measurements on a powder of YBa2Cu3O7-x. We conclude that the structure results from interactions among the grains and is not an intrinsic property of the compounds. Flux creep associated with this structure is found to be proportional to ln(t) over three decades of observation time. [ABSTRACT FROM AUTHOR]

Focuses on the sputtered permanent-magnet thin films which may offer an alternative to bulk permanent magnets for biasing microwave magnetic devices. Disadvantage of a film of uniform thickness.