The magnetoelectrochemical switch

In the field of spintronics, the archetype solid-state two-terminal device is the spin valve, where the resistance is controlled by the magnetization configuration. We show here how this concept of spin-dependent switch can be extended to magnetic electrodes in solution, by magnetic control of their chemical environment. Appropriate nanoscale design allows a huge enhancement of the magnetic force field experienced by paramagnetic molecular species in solutions, which changes between repulsive and attractive on changing the electrodes' magnetic orientations. Specifically, the field gradient force created within a sub-100-nm-sized nanogap separating two magnetic electrodes can be reversed by changing the orientation of the electrodes' magnetization relative to the current flowing between the electrodes. This can result in a breaking or making of an electric nanocontact, with a change of resistance by a factor of up to 103. The results reveal how an external field can impact chemical equilibrium in the vicinity of nanoscale magnetic circuits

Design and test of new high Q microresonators fabricated by UV-LIGA

International audienceWe report in this paper the study of a new metallic microresonator realized by UV-LIGA technique. This kind of device is excited electrostatically and takes advantage of the contour modes or Lame-modes of the structure. Design methods of such device are presented and simulated with a Finite Element Program. Details on the microfabrication process are also presented. The vibration modes are detected with an optical bench set-up and preliminary electrical results are presented. A comparison between experiments and numerical predictions are finally discussed

Conception de microrésonateurs à mode de Lamé

National audienc

Simulation and Characterization of High Q Microresonators Fabricated by UV – LIGA

Vol. 1, Chapter 7: Applications: MEMS, SensorsInternational audienceThis paper is devoted to a study on a new metallic microresonator realized by UV-LIGA technique. This device is excited electrostatically and takes advantage of the contour modes or Lamé-modes of the structure. Design methods of such device are presented and validated by the use of Finite Element Analysis (FEA). Details on the fabrication process are also exposed. The vibration modes are detected with an optical interferometer and preliminary results are presented. A comparison between experiments and numerical predictions are finally discussed

Modeling and characterization of Lame-mode microresonators realized by UV-LIGA

We report in this paper the study of a new metallic microresonator realized by UV-LIGA technique. This kind of device is excited electrostatically and takes advantage of the contour modes or Lame-modes of the structure. Design methods of such device are presented and simulated with a Finite Element Program. Details on the microfabrication process are also presented. The vibration modes are detected with an optical bench setup and preliminary electrical results are presented. A comparison between experiments and numerical predictions are finally discussed

Characteristics of torsional resonator with two degrees of freedom fabricated by UV-LIGA

International audienc

Pulmonary Sarcoidosis following Etanercept Treatment for Ankylosing Spondylitis: A Case Report and Review of the Literature

Antitumor necrosis factor therapies have revolutionized the treatment of some inflammatory diseases. However, the use of these agents is associated with the development of many paradoxical autoimmune diseases. Less well-recognized is the association with sarcoidosis. We report a 55-year-old female with long-standing ankylosing spondylitis who developed persistent dry cough and dyspnea while receiving etanercept therapy. High-resolution computed tomography scanning showed mediastinal lymphadenopathy and multiple nodules in both lung fields developed two months after the administration of etanercept. Lymph node biopsy was not practicable. Histopathological examination of minor salivary gland biopsy revealed noncaseating granulomata, and the serum angiotensin-converting enzyme was very elevated. All infectious studies were negative. Etanercept was discontinued plus a course of corticosteroids with a clinical improvement, and a follow-up high-resolution computed tomography scanning 4 months later showed evident regression of mediastinal lymph nodes and pulmonary nodules. Potential pathogenic mechanisms of this paradoxical effect of tumor necrosis factor-alpha blocking agents are discussed

Direct Writing of High Frequency Surface Acoustic Wave Devices on Epitaxial Pb(Zr_0.20Ti_0.80)O₃ Thin Layers Using Focus Ion Beam Etching

The possibility to manufacture single devices allowing the 10 GHz threshold to be largely overcome has been demonstrated using Electron-beam lithography. In this paper, we propose an original alternative to lithographic techniques based on the Focused Ion Beam etching technique to fabricate SAW devices by directly "writing" the electrode pattern in the metal overlay. We also explore the RF capabilities of epitaxial Pb(Zr0.20Ti0.80)O-3 (PZT) thin films deposited onto SrTiO3 single crystal substrates. We found that guided waves can be efficiently excited and detected at frequencies ranging from 3 to 5 GHz. Theory/experiment assessment shows a good predictability of the waves characteristics

Probing Spin Wave Diffraction Patterns of Curved Antennas

International audienceWe report on the dependence of curvilinear shaped coplanar waveguides on the near-field diffraction patterns of spin waves propagating in perpendicularly magnetized thin films. Implementing the propagating spin waves spectroscopy techniques on either concentrically or eccentrically shaped antennas, we show how the link budget is directly affected by the spin wave interference, in good agreement with near-field diffraction simulations. This work demonstrates the feasibility to inductively probe a magnon interference pattern with a resolution down to 1µm 2 , and provides a methodology for shaping spin wave beams from an antenna design. This methodology is successfully implemented in the case study of a spin wave Young's interference experiment

Vibration Maps of Capacitive Micromachined Ultrasonic Transducers by Laser Interferometry

In this letter, a 1.8-mm 1.8-mm capacitive micromachined ultrasonic transducer (CMUT) element is experimentally characterized by means of optical measurements. Optical displacement measurements provide information on the resonant behavior of the single membranes and also allow us to investigate the dispersion in the frequency spectrum of adjacent membranes. In addition, higher order mode shapes are observed, showing that either symmetrical or asymmetrical modes are excited in CMUT membranes. Laser interferometry vibration maps, combined with quantitative displacement measurements, provide information about the quality and repeatability of the fabrication process, which is a basic requirement for 2-D array fabrication for ultrasound imaging