Abstract: A thin-film magnetic device comprises, on a substrate, a composite assembly deposited by cathode sputtering and consists of a first layer made of a ferromagnetic material with a high rate of spin polarization, the magnetization of which is in plane in the absence of any electric or magnetic interaction, a second layer made of a magnetic material with high perpendicular anisotropy, the magnetization of which is outside the plane of said layer in the absence of any electric or magnetic interaction, and coupling of which with said first layer induces a decrease in the effective demagnetizing field of the entire device, a third layer that is in contact with the first layer via its interface opposite to that which is common to the second layer and made of a material that is not magnetic and not polarizing for electrons passing through the device.

Abstract: The magnetic device comprises a least two layers made of a magnetic material that are separated by at least one interlayer made of a non-magnetic material. The layers made of a magnetic material each have magnetization oriented substantially perpendicular to the plane of the layers. The layer of non-magnetic material induces an antiferromagnetic coupling field between the layers made of a magnetic material, the direction and amplitude of this field attenuating the effects of the ferromagnetic coupling field of magnetostatic origin that occurs between the magnetic layers.

Abstract: An information storage medium with an array of laterally magnetised dots, as well as a process for producing this medium is disclosed. Each dot (2) contains at least one magnetic domain formed by a thin layer (4) of at least a magnetic material laterally covering this flat material and deposited at oblique incidence relative to the normal (z) to the plane (6) of the array. The invention applies in particular to computer hard drives.

Abstract: The invention relates to a method of operating a spin-transfer torque structure to generate voltage oscillations, said structure comprising a first layer of magnetic material having a fixed magnetization vector, a spacer of non magnetic material and a second layer of magnetic material having a free magnetization vector. The method includes the application of a current (jop) through said structure and a magnetic field (Hext) in the plane of the second layer. It makes use of a region of bistability and hysteretic behaviour to trigger and stop the voltage oscillations.

Abstract: The present invention relates to a method of fabricating a nanostructure, comprising the following steps: prestructuring a substrate (1) adapted to receive the nanostructure to form a nanorelief (2) on the substrate, the nanorelief having flanks (4) extending from a bottom (1a) of the substrate and a top face (3) extending from said flanks, and then depositing on the substrate pre-structured in this way a single layer or multilayer coating intended to form the nanostructure; and further comprising: adding to the prestructured substrate or to the coating a separation layer adapted to enable separation of the coating and the substrate by external action of mechanical, thermomechanical or vibratory type; and exerting this external action on the substrate and/or the coating to recover selectively a top portion of the coating by separating it from the top face of the nanorelief so that this top portion constitutes some or all of the nanostructure.

Abstract: The memory comprises, on a semi-conducting substrate, a matrix of cells arranged in lines and columns and each designed to store an information bit. Each cell of a column comprises a magnetic tunnel junction having a line terminal and a column terminal respectively connected to a line conductor and, by means of a transistor, to a first column conductor associated to said column and to a first adjacent column. A gate of the transistor is connected to a gate conductor. The column terminal of each tunnel junction of said column is connected, by means of an additional transistor, to a second column conductor associated to said column and to a second adjacent column. A gate of the additional transistor is connected to an additional gate conductor. The two transistors associated to a cell can have a common electrode.

Abstract: Magnetoresistive device comprising a spin valve formed from a stack of layers including at least two magnetic layers for which a relative orientation of their magnetisation directions are capable varying under influence of a magnetic field; at least one discontinuous dielectric or semiconducting layer with electrically conducting bridges at least partially passing through a thickness of the dielectric or semiconducting layer, the bridges configured to locally concentrate current that passes transversely through the stack; and means for circulating a current in the spin valve transverse to the plane of the layers, characterised in that the dielectric or semiconducting layer with electrically conducting bridges is arranged inside one of the magnetic layers.

Abstract: The magnetic device comprises a magnetic device comprising a magnetoresistive tunnel junction (100), itself comprising: a reference magnetic layer (120) having magnetization in a direction that is fixed; a storage magnetic layer (110) having magnetization in a direction that is variable; and an intermediate layer (130) acting as a tunnel barrier that is essentially semiconductor or electrically insulating and that separates the reference magnetic layer (120) from the storage magnetic layer (110). The potential profile of the intermediate layer (130) is asymmetrical across the thickness of said layer (130) so as to produce a current response that is asymmetrical as a function of the applied voltage. The device is applicable to magnetic random access memories.

Abstract: This magnetic element with thermally-assisted writing using a field or spin transfer comprises a magnetic reference layer referred to as the “trapped layer”, the magnetisation of which is in a fixed direction; a magnetic storage layer called the “free layer” having a variable magnetisation direction and consisting of a layer made of a ferromagnetic material with magnetisation in the plane of the layer and magnetically coupled to a magnetisation-trapping layer made of an antiferromagnetic material; a semiconductor or an insulating layer with confined-current-paths sandwiched between the reference layer and the storage layer. At least one bilayer consisting respectively of an amorphous or quasi-amorphous material and a material having the same structure or the same crystal lattice as the antiferromagnetic layer is placed in the storage layer between ferromagnetic layer which is in contact with the semiconductor or insulating layer with confined-current-paths and antiferromagnetic layer.

Abstract: The device comprises two magnetoresistive elements (10, 20) placed relative to each other in magnetostatic interaction in such a manner that a magnetic flux passing between these elements (10, 20) closes through soft ferromagnetic layers (26, 27) of said elements (10, 20). A write device (15) is associated with the elements (10, 20) to control the magnetization of each soft layer (26, 27). A read conductor line (11, 12, 13, 14) is associated with each magnetoresistive element (10, 20) to detect the magnetic state of the soft layer (26, 27) by measuring the corresponding magnetoresistance. The soft ferromagnetic layers (26, 27) of the elements (10, 20) remain oriented substantially in antiparallel relative to each other, while the hard ferromagnetic layers (24) of said elements (10, 20) are oriented substantially in parallel.

Abstract: The present invention relates to a magnetoresistive sensor comprising a first pinned-magnetization magnetic layer (410), called pinned layer, and a free-magnetization magnetic layer (430), called sensitive layer, of which the magnetization, in the absence of an external field, is substantially orthogonal to the magnetization of the pinned layer, said pinned and sensitive layers being separated by a first separating layer (420) for magnetic uncoupling. The sensor further comprises a layer (440), called lateral coupling layer, located on the side of the sensitive layer opposite that of the separating layer, and serving to control the lateral spin transfer.

Abstract: The device successively comprises a first electrode (12), a magnetic reference layer (1), a tunnel barrier (3), a magnetic storage layer (4) and a second electrode (13). At least one first thermal barrier is arranged between the storage layer (4) and the second electrode (13) and is formed by a material having a thermal conductivity lower than 5W/m/° C. A second thermal barrier can be formed by a layer arranged between the first electrode (12) and the reference layer (1). A write phase of the method comprises flow of an electric current (I1), through the tunnel junction, from the storage layer (4) to the reference layer (1), whereas a read phase comprises flow of an electric current (I2) in the opposite direction.

Abstract: The present invention relates to a magnetoresistive sensor comprising a first pinned-magnetization magnetic layer (410) and a second free-magnetization magnetic layer (430), called sensitive layer, separated by first separating layer (420) for magnetic uncoupling. The sensor further comprises a second pinned-magnetization magnetic layer (450), separated from said sensitive layer by a second separating layer (440) for magnetic uncoupling, the first and second separating layers being located on either side of said sensitive layer, and the respective magnetizations of the first pinned-magnetization magnetic layer and of the sensitive layer, in the absence of an external field, being substantially orthogonal. The orientation of the magnetization of the second pinned layer is selected.

Abstract: A magnetoresistive device with a spin valve formed from a stack of layers including at least two magnetic layers for which the relative orientation of their magnetization directions can vary under the influence of a magnetic field, and comprising means of circulating a current in the spin valve transverse to the plane of the layers. The spin valve comprises at least one discontinuous dielectric or semiconducting layer in the stack, with electrically conducting bridges passing through the thickness of the dielectric or semiconducting layer, these bridges being designed to locally concentrate the current that passes transversely through the stack. Application particularly suitable for magnetic read heads, and random access memories.

Abstract: This magnetic memory with a thermally-assisted write, every storage cell of which consists of at least one magnetic tunnel junction, said tunnel junction comprising at least: one magnetic reference layer, the magnetization of which is always oriented in the same direction at the time of the read of the storage cell; one so-called “free” magnetic storage layer, the magnetization direction of which is variable; one insulating layer sandwiched between the reference layer and the storage layer. The magnetization direction of the reference layer is polarized in a direction that is substantially always the same at the time of a read due to magnetostatic interaction with another fixed-magnetization layer called the “polarizing layer”.

Abstract: This radio-frequency oscillator includes a magnetoresistive device in which a spin-polarised electric current flows. This device comprises a stack of at least a first so-called “anchored” magnetic layer having a fixed magnetisation direction, a second magnetic layer, an amagnetic layer inserted between the above-mentioned two layers, intended to ensure magnetic decoupling of said layers. The oscillator also comprises means of causing a flow of electrons in said layers perpendicular to these layers and, if applicable, of applying an external magnetic field to the structure. The second magnetic layer has an excitation damping factor at least 10% greater than the damping measured in a simple layer of the same material having the same geometry for magnetic excitation having wavelengths equal to or less than the extent of the cone or cylinder of current that flows through the stack that constitutes the magnetoresistive device.

Abstract: A system and method for writing to a magnetic memory written in a thermally assisted manner, each memory point formed by a magnetic tunnel junction, and having a substantially circular cross-section of the memory which is parallel to the plane of the layers forming the tunnel junction. The tunnel junction includes at least a trapped layer with a fixed magnetisation direction, a free layer with a variable magnetisation direction with an insulating layer arranged there between. The free layer is formed from at least one soft magnetic layer and a trapped layer, with the two layers being magnetically coupled by contact. During read operations and at rest, the operating temperature of the memory is lower than the blocking temperature of the free and trapped layers, respectively.

Abstract: This magnetic multilayer device comprises, on a substrate, an alternating sequence of magnetic metallic layers M and oxide, hydride or nitride layers O. The number of layers M equals at least two. The layers M are continuous. There is interfacial magnetic anisotropy perpendicular to the plane of the layers at the level of the M/O interfaces.

Abstract: This magnetic device comprises a least two layers made of a magnetic material that are separated by at least one interlayer made of a non-magnetic material. Said layers made of a magnetic material each have magnetization oriented substantially perpendicular to the plane of said layers. Said layer of non-magnetic material is capable of inducing an antiferromagnetic coupling field between said layers made of a magnetic material, the direction and amplitude of this field making it possible to attenuate the effects of the ferromagnetic coupling field of magnetostatic origin that occurs between said magnetic layers.

Abstract: A thin-film magnetic device comprises, on a substrate, a composite assembly deposited by cathode sputtering and consists of a first layer made of a ferromagnetic material with a high rate of spin polarisation, the magnetisation of which is in plane in the absence of any electric or magnetic interaction, a second layer made of a magnetic material with high perpendicular anisotropy, the magnetisation of which is outside the plane of said layer in the absence of any electric or magnetic interaction, and coupling of which with said first layer induces a decrease in the effective demagnetising field of the entire device, a third layer that is in contact with the first layer via its interface opposite to that which is common to the second layer and made of a material that is not magnetic and not polarising for electrons passing through the device.