Romolo Marcelli

Nonlinear Microwave Signal Processing: Towards a New Range of Devices

I: Classical and Novel Nonlinear Effects, Applications in Different Physcial Systems. 1. Notes on the Problem of Magnetization Reversal R. Arias, et al. 2. An Overview of Nonlinear Microwave and Millimeter Wave Generation in Magnetic, Acoustic and Electromagnetic Distributed Nonlinear Physical Systems M. Dragoman, D. Dragoman. 3. Inhomogeneous Internal Field Distribution in Planar Microwave Ferrite Devices M. Parda-Horvath, Guobao Zheng. 4. Design of Nonlinear Transmission Lines: GaAs and Magnetic Film Devices R. Marcelli, et al. 5. Nonlinear Dynamics of Optical Solitons S. Wabnitz. II: Spin Wave Instabilities. 6. Theory of Spin-Wave Interactions in Heisenberg Ferromagnetic Thin Films M.G. Cottam, N.J. Zhu. 7. Kinetic Instability and Bose Condensation of Magnons - The Sources of Controlled Microwave Emission from Magnetic Crystals G.A. Melkov, A.Yu. Taranenko. 8. Exchange Spin Waves in Nonuniform Films of Yttrium Ion Garnet A.G. Temiryazev, et al. 9. Parametric Instability of Spin Waves in Ferromagnets under a Spatially Localized Longitudinal Magnetic Pump Field Yu.V. Gulyaev, et al. 10. Spatial Nonuniformity and Spin Wave Turbulence in Antiferromagnet A.I. Smirnov. III: Solitons and Chaos. 11. Microwave Solitons in Magnetic Media: A Review of Fundamental Properties A.D. Boardman, et al. 12. Soliton-like Packets of Parametrically Coupled Spin Waves A.F. Popkov, et al. 13. Macroscopic Quantum Tunneling of Solitons in Ultrathin Films A.K. Zvezdin, V.V. Dobrovitski. 14. Controlling Chaos in Thin YIG Films at Microwave Frequencies D.W. Peterman, P.E. Wigen. 15. Suppressing and Controlling Chaos in Spin-Wave Instabilities T. Bernard, et al. IV: Magneto-Optic Interaction: Nonlinear Effects and Devices. 16. Applications of Magnetic Garnet Films in Optical Communication H. Dotsch, et al. 17. Interactions between Optical Guided Modes and Nonlinear Magnetostatic Waves D.D. Stancil, A. Prabhakar. 18. Integrated Magnetooptic Devices with Applications to RF Signal Processing and Communications C.S. Tsai.

Quantitative sub-surface and non-contact imaging using scanning microwave microscopy

The capability of scanning microwave microscopy for calibrated sub-surface and non-contact capacitance imaging of silicon (Si) samples is quantitatively studied at broadband frequencies ranging from 1 to 20 GHz. Calibrated capacitance images of flat Si test samples with varying dopant density (10(15)-10(19) atoms cm(-3)) and covered with dielectric thin films of SiO2 (100-400 nm thickness) are measured to demonstrate the sensitivity of scanning microwave microscopy (SMM) for sub-surface imaging. Using standard SMM imaging conditions the dopant areas could still be sensed under a 400 nm thick oxide layer. Non-contact SMM imaging in lift-mode and constant height mode is quantitatively demonstrated on a 50 nm thick SiO2 test pad. The differences between non-contact and contact mode capacitances are studied with respect to the main parameters influencing the imaging contrast, namely the probe tip diameter and the tip-sample distance. Finite element modelling was used to further analyse the influence of the tip radius and the tip-sample distance on the SMM sensitivity. The understanding of how the two key parameters determine the SMM sensitivity and quantitative capacitances represents an important step towards its routine application for non-contact and sub-surface imaging.

Broadband RF-MEMS Based SPDT

A broadband single pole double throw (SPDT) switch has been developed for use in the range of 0 to 30 GHz. The switch consists of a cascade of a MEMS ohmic series and a capaci-tive shunt switch with floating electrode in each branch. It is manufactured on high-resistive silicon using surface micro-machining technology. The SPDT switch provides an insertion loss better than -0.6 dB, return loss smaller than -20dB, and isolation better than -40 dB in nearly the whole band. A switching voltage around 50 V is needed. The switch is used as a building block for more complex switching networks. The fabrication process is described and the measured RF-performances are reported and discussed. A failure analysis exhibits a lifetime up to 109 actuations

Magnetostatic wave single and multiple stage resonators

A review of the design criteria for magnetostatic volume wave band-pass resonating filters will be presented. The prediction of the radiation resistance and of the reactance of microstrip lines coupled to magnetic films in grounded configurations will be used to model straight edge resonators by means of lumped elements. As an application, the performances of tunable single and multiple stage narrow-band filters working at X-band will be evaluated.

RF-MEMS SPDT switch on silicon substrate for space applications

The paper illustrates the activity carried out under an ESA contract for the development of a miniaturized RF-MEMS SPDT switch and switch matrix using micromachining technology on a silicon substrate for power applications. A manufacturing procedure, based on an eight masks process, has been set up. At present, a broadband single-pole-double-throw (SPDT) switch operating in the 0-30 GHz frequency range has been fabricated and measured. Isolation of about -40 dB and insertion loss better than -0.7 dB have been obtained.

Dielectric charging in microwave microelectromechanical Ohmic series and capacitive shunt switches

The charging of the dielectric used for the actuation in microelectromechanical system (MEMS) devices is one of the major failure sources for switches based on this technology. For this reason, a better understanding of such an effect is vital to improve the reliability for both ground and space applications. In this paper, the expected response of MEMS switches to unipolar and bipolar dc actuation voltages has been measured and modeled. Two configurations of MEMS switches, namely, an Ohmic series and a shunt capacitive one designed for microwave applications, have been studied as a test vehicle for charging effects related to the dc actuation pads. The recorded data have been interpreted mainly through the Poole–Frenkel effect due to charge injection when a high voltage is applied to the dielectric layer. Metal-Insulator-Metal (MIM) structures have been also considered as a complementary information for the response of the dielectric material.

An equivalent-circuit model for shunt-connected coplanar microelectromechanical system switches for high frequency applications

In this paper, a circuit model to predict the microwave response of a shunt-connected capacitive microelectromechanical coplanar switch is proposed. The numerical values of the lumped elements composing the equivalent circuit are computed by means of a fully analytic approach. In particular, the contribution of resistive and inductive parasitic elements has been evaluated by using closed-form expressions. Configurations characterized by different technological solutions have been obtained and modeled. Simulations performed with the proposed approach correlate very well with actual measurements.

A magnetostatic wave oscillator for data relay aatellite

In this paper the design, realization and test of a magnetostatic wave oscillator working at 14 GHz for possible use in data relay systems for ground and satellite applications is presented. Power levels as high as 4 dBm and a tuning bandwidth of 500 MHz have been designed and obtained.

Modulational instability of surface magnetostatic waves in ferromagnetic films

Abstract A modulational instability of the surface magnetostatic wave has been experimentally observed. It was found that, in the spectrum of an intense magnetostatic wave propagating in an in-plane magnetized yttrium-iron-garnet film with a single metallic ground plane, symmetric satellite frequencies appeared when the power of the initial wave was above a certain threshold value. Three-magnon decay processes having a low power threshold with respect to four-magnon self-action processes were forbidden by the conservation laws for the momentum and energy. The calculated modulation frequency and power threshold are in a good agreement with measured values.

Analysis of a transmission mode scanning microwave microscope for subsurface imaging at the nanoscale

We present a comprehensive analysis of the imaging characteristics of a scanning microwave microscopy (SMM) system operated in the transmission mode. In particular, we use rigorous three-dimensional finite-element simulations to investigate the effect of varying the permittivity and depth of sub-surface constituents of samples, on the scattering parameters of probes made of a metallic nano-tip attached to a cantilever. Our results prove that one can achieve enhanced imaging sensitivity in the transmission mode SMM (TM-SMM) configuration, from twofold to as much as 5× increase, as compared to that attainable in the widely used reflection mode SMM operation. In addition, we demonstrate that the phase of the S21-parameter is much more sensitive to changes of the system parameters as compared to its magnitude, the scattering parameters being affected the most by variations in the conductivity of the substrate. Our analysis is validated by a good qualitative agreement between our modeling results and experimen...