Abstract: An energy harvester having a converter suitable for converting a variation of the energy to be harvested into a corresponding excess of electrical charges. There is a circuit for collecting the excess of electrical charges, the circuit is equipped with a controllable switch and a control device for the switch designed to control the switching of this switch to its closed position. The control device is suitable for exerting a force which stresses the electrical contacts towards one another. The force varies continually as a function of the quantity of electrical charges present on the first terminal and bringing the electrical contacts to bear on one another only when the excess of electrical charges exceeds a predetermined threshold, and/or for ionizing the electrically insulating medium to produce an electrical arc between the two electrical contacts only when the excess of electrical charges exceeds the predetermined threshold.

Abstract: The radio-frequency identification tag comprises: a ground plane made of an electrically conductive material, and an actuator made of a transducer material adapted to convert a variation of a physical quantity into a mechanical displacement of the ground plane between first and second positions when the physical quantity crosses a predetermined threshold in order to indicate this event to the reader, the transducer material being selected from a group consisting of a thermal shape-memory material, a magnetostrictive material and a magnetic shape-memory material. The transducer material is also an electrically conductive material. The ground plane and the actuator are both formed by a single strip made of this transducer material and a mobile portion of which moves relative to an antenna between the first and second positions when the physical variable crosses the predetermined threshold.

Abstract: A converter for converting a variation in energy to be recovered, the converter including: a transducer layer extending essentially parallel to a reference plane and configured to transform the variation in the energy to be recovered into a mechanical deformation, the transducer layer comprising: a plurality of first blocks made from a magnetostrictive or shape-memory material, the first blocks being delimited in relation to one another by side edges, and regions that do not contain the material of the first block, the regions being inserted between the side edges of the first blocks; and a piezoelectric layer secured to the transducer layer. Each of the first blocks has a preferential axis of deformation parallel to the reference plane.

Abstract: A converter including a first transducer that can lengthen inside at least a first deformation zone and simultaneously shrink inside at least a different second deformation zone. Inner faces of second and third electromechanical transducers are secured respectively, with no degree of freedom, substantially to the first and second deformation zones of the layer of the first transducer. The third transducer differs from the second transducer by the polarization of its layer of piezoelectric material in a different direction to polarization of the layer of piezoelectric material of the second transducer and/or by existence of a separation that mechanically and electrically insulates a first electrode of the third transducer from a first electrode of the second transducer located on a same side of the layer of piezoelectric material.

Abstract: A converter including a transducer layer which moves anchoring points to deform a piezoelectric diaphragm by bending. The converter includes a rigid arm between each anchoring point and a point for securing to the piezoelectric diaphragm to which it is attached, the rigid arm being tensioned between the anchoring point and the securing point and configured to transform movement of the anchoring points into a movement that deforms the piezoelectric diaphragm between bent and less bent positions. The securing point is located at the mid-point when the ends of the piezoelectric diaphragm are secured, with no degree of freedom, in a frame, and the securing point is located at one end of the piezoelectric diaphragm when the mid-point is secured, with no degree of freedom, in the frame.

Abstract: A magnetic field sensor has a magnetoresistive rod having a stack of stacked layers that include a pinned layer having a fixed magnetization direction almost perpendicular to a longitudinal direction, a free layer comprising a magnetostrictive material having a coefficient of magnetostriction greater than 20 ppm to 25° C. and a longitudinal axis of easiest magnetization, the magnetization changing when the free layer is exposed to a magnetic field, a non-magnetic spacer layer interposed between the free and pinned layers to form a tunnel junction or spin valve, and a stress-generating layer for exerting uniaxial stress essentially such that a product of stress and magnetostriction coefficient is greater than 500 ppm·MPa at 25° C. The rod's length is at least ten times its greatest width.

Abstract: An artificial magnetic conductor having a surface impedance greater than 100?, includes a ground plane, and a frequency-selective surface that is transparent for certain wavelengths and reflective for a range of wavelengths. The frequency-selective surface includes an array of conductive resonant elements arranged alongside one another in at least two different directions parallel to the ground plane. Each of these conductive resonant elements includes a sub-layer of ferromagnetic material having a relative permeability greater than 10 at a frequency of 2 GHz and having a thickness less than the skin thickness of the ferromagnetic material.

Abstract: A radio tag capable of indicating to a reader, via a wireless link, that a variation in energy has crossed a predetermined threshold, this variation in energy being chosen from the group made up of a variation in the temperature of the radio tag and a variation in the magnetic field in which the radio tag is immersed. This radio tag includes transducer material chosen from a group made up of a thermal shape-memory material, a magnetostrictive material and a magnetic shape-memory material. This transducer material is deposited and affixed without any degree of freedom onto a substrate or an antenna of the radio tag to form, with the substrate or the antenna, a multilayer structure which flexurally deforms the antenna between a bent conformation and a less bent conformation when the energy variation crosses the predetermined threshold.

Abstract: A process of manufacturing component with a composite film including a matrix made of thermoplastic polymer and particles inside this matrix. This process includes heating the composite film in order for its temperature to exceed the glass transition temperature of its matrix, then when the composite film is softened, flattening an external face of the composite film by a smooth face resting directly over the whole of this external face, this smooth face forming part of the front face of a flexible membrane, the whole of the rear face of which, located on the side opposite the front face, is pushed against the composite film by a fluid, then cooling the composite film below the glass transition temperature, then withdrawing the membrane in order to mechanically separate its front face from the external face of the composite film.

Abstract: Process for the transfer of a composite film onto a flexible polymer membrane in which the composite film comprises a matrix made of thermoplastic polymer and particles. This process comprises the following operations: 1) the movement of the membrane into a position in which it closes up, in a way leaktight to a fluid, an opening of a reservoir and a first zone of its front face is directly in contact on an external face of the composite film, 2) the heating of the composite film, so as to soften it, then 3) when the composite film is softened, a fluid inside the reservoir uniformly compresses the first zone against the external face of the composite film in order to adhesively bond this first zone to this external face, then 4) the movement of the membrane to a retracted position in order to separate, from the rigid substrate, the portion of the composite film adhesively bonded to the first zone.

Abstract: A planar antenna with widened bandwidth comprises at least one first conducting element disposed above an earth plane and separated from the latter, and means for exciting said at least first conducting element, configured to excite two distinct orthogonal resonant modes, wherein said at least first conducting element is embodied by a substrate comprising at least one thin layer of an anisotropic material with relative permeability of greater than 10 for 2 GHz. The antenna applies notably to mobile communications terminals.

Abstract: An energy harvester includes a circuit for collecting an excess of electrical charges on a first connection terminal, wherein the circuit is equipped with a first controllable mechanical switch, and a control device for the first switch. There is a transducer suitable for directly transforming, without consuming the excess of electrical charges present on the first connection terminal, the variation of the energy to be harvested into a mechanical deformation which displaces the first switch from its open position to its closed position.

Abstract: An electricity generator including a first converter suitable for converting a variation of an energy to be harvested into a corresponding excess of electrical charges. The generator includes a circuit for collecting the excess of electrical charges, the circuit has a first controllable mechanical switch, and a control device for the first switch designed to control the switching of the switch to its closed position when the excess of electrical charges exceeds a first predetermined threshold. The switch is a magnetic switch and the control device comprises a variable magnetic field source which controls the switching of the first switch to its closed position only at the time when the excess of electrical charges exceeds the first predetermined threshold.

Abstract: An energy harvester having a converter suitable for converting a variation of the energy to be harvested into a corresponding excess of electrical charges. There is a circuit for collecting the excess of electrical charges, the circuit is equipped with a controllable switch and a control device for the switch designed to control the switching of this switch to its closed position. The control device is suitable for exerting a force which stresses the electrical contacts towards one another. The force varies continually as a function of the quantity of electrical charges present on the first terminal and bringing the electrical contacts to bear on one another only when the excess of electrical charges exceeds a predetermined threshold, and/or for ionizing the electrically insulating medium to produce an electrical arc between the two electrical contacts only when the excess of electrical charges exceeds the predetermined threshold.

Abstract: A radio-frequency device comprises magneto-dielectric elements. At least one of these elements comprises a composite thin film. This film comprises a magnetic material offering permeability above 10 at 1 GHz and a dielectric material offering permittivity above 10 at 1 GHz.

Abstract: According to this method for producing a magnetic tunnel junction, a film of a dielectric material capable of acting as a tunnel barrier is deposited between two nanocrystalline or amorphous magnetic films. The dielectric material constituting the tunnel barrier consists of an at least partially crystalline perovskite, and said material is deposited by ion beam sputtering in a vacuum chamber.

Abstract: A magnetic field vector sensor includes a substrate parallel to a plane, a support mobile relative to it and rotatable about a vertical rotation axis perpendicular to it, a magnetic field source generating a field having a moment in a non-perpendicular direction, the source being fixed to the support with no degree-of-freedom to exert torque on the support when a field to be measured is present, the field being non-collinear with the moment, a transducer to convert torque exerted on the support into a field amplitude of a component of the field along a measurement axis in the plane, wherein the source comprises a magnetostrictive permanent magnet for generating the field having a moment whose direction varies with stress on the magnet, and wherein the sensor further comprises a controllable device to reversibly modify the moment direction, and a stress generator to vary stress and hence moment direction.

Abstract: A planar antenna with widened bandwidth comprises at least one first conducting element disposed above an earth plane and separated from the latter, and means for exciting said at least first conducting element, configured to excite two distinct orthogonal resonant modes, wherein said at least first conducting element is embodied by a substrate comprising at least one thin layer of an anisotropic material with relative permeability of greater than 10 for 2 GHz. The antenna applies notably to mobile communications terminals.

Abstract: This variable-response magnetic radiofrequency device integrated into a substrate comprises: a beam that is mobile relative to the substrate having, at each end, a transversal part mechanically anchored to the substrate and at least one central arm connecting the transversal parts to each other, at least one of the transversal parts being made out of a piezoelectric material, actuating electrodes associated with the piezoelectric material to apply a stress on the central arm, a magnetic element directly deposited on the central arm whose permeability varies as a function of the stress, and a conductive strip comprising a central part fixed to an upper face of the magnetic element opposite the lower face of this magnetic element pointed towards the central arm.

Abstract: An artificial magnetic conductor having a surface impedance greater than 100 ?, includes a ground plane, and a frequency-selective surface that is transparent for certain wavelengths and reflective for a range of wavelengths. The frequency-selective surface includes an array of conductive resonant elements arranged alongside one another in at least two different directions parallel to the ground plane. Each of these conductive resonant elements includes a sub-layer of ferromagnetic material having a relative permeability greater than 10 at a frequency of 2 GHz and having a thickness less than the skin thickness of the ferromagnetic material.