Abstract:
L'invention concerne un dispositif magnétique comportant une couche de référence (2) dont la direction d'aimantation est fixe et une couche de stockage (3) dont la direction d'aimantation est variable. Dans un mode écriture, la direction d'aimantation de la couche de stockage (3) est modifiée de façon à stocker un " 1 " ou un " 0 " dans cette couche de stockage. Dans un mode lecture, la résistance du dispositif magnétique est mesurée de façon à savoir ce qui est stocké dans la couche de stockage (3). Le dispositif magnétique est particulièrement remarquable en ce qu'il comporte en outre une couche de contrôle (4) dont la direction d'aimantation est variable. La direction d'aimantation de la couche de contrôle (4) est contrôlée de façon à augmenter l'efficacité du transfert de spin lorsque l'on veut écrire dans la couche de stockage (3) et à diminuer l'efficacité du transfert de spin lorsque l'on veut lire l'information contenue dans la couche de stockage (3) sans modifier cette information.
Abstract:
The present invention is notably directed to spin logic devices (100) and related methods. The devices (100) comprise: an electron confinement layer (8, 87, 89) confining an electron gas or 2DEG in a two- dimensional area subtended by a direction x and a direction y , the latter perpendicular to the former, the spin logic device configured for the 2DEG to support a persistent spin helix or PSH formed therein with a given spin component oscillating with periodicity λ along direction x but not oscillating along direction y ; and a majority logic circuit (14), said circuit comprising: one or more input devices (1, 1a, 1b, 1c, 1c1, 1c2, 1d), energizable to create respective local spin-polarizations (3) of the 2DEG in respective first regions (10) of the confinement layer, such as to form respective PSHs; and an output device (4), configured to detect, in a second region (40) of the confinement layer, an average spin-polarization (6) of the 2DEG resulting from one or more local spin-polarizations (3) created by the one or more input devices and diffused through one or more resulting PSHs, respectively, wherein a projection of a distance ( d ) between the second region (40) and any one of the first regions (1) onto said direction x is equal to n λ/ a , n integer, a equal to 2 or 4.
Abstract:
A magnetic memory cell and a magnetic memory incorporating the cell are described. The magnetic memory cell includes at least one magnetic element and at least one non-planar selection device. The magnetic element(s) are programmable using write current(s) driven through the magnetic element. The magnetic memory may include a plurality of magnetic storage cells, a plurality of bit lines corresponding to the plurality of magnetic storage cells, and a plurality of source lines corresponding to the plurality of magnetic storage cells.
Abstract:
A spin injection device and spin transistor including a spin injection device. A spin injection device includes different semiconductor materials and a spin-polarizing ferromagnetic material there between. The semiconductor materials may have different crystalline structures, e.g., a first material can be polycrystalline or amorphous silicon, and a second material can be single crystalline silicon. Charge carriers are spin-polarized when the traverse the spin-polarizing ferromagnetic material and injected into the second semiconductor material. A Schottky barrier height between the first semiconductor and ferromagnetic materials is larger than a second Schottky barrier height between the ferromagnetic and second semiconductor materials. A spin injection device may be a source of a spin field effect transistor.
Abstract:
A multi-state spin-torque transfer magnetic random access memory (STTMRAM) is formed on a film and includes a first magnetic tunneling junctions (MTJ) having a first fixed layer, a first sub-magnetic tunnel junction (sub-MTJ) layer and a first free layer. The first fixed layer and first free layer each have a first magnetic anisotropy. The STTMRAM further includes a non-magnetic spacing layer formed on top of the first MTJ layer and a second MTJ formed on top of the non-magnetic spacing layer. The second MTJ has a second fixed layer, a second sub-MTJ layer and a second free layer. The second fixed and second free layers each have a second magnetic anisotropy, wherein at least one of the first or second magnetic anisotropy is perpendicular to the plane of the film.
Abstract:
Techniques and device designs associated with devices having magnetically shielded magnetic or magnetoresistive tunnel junctions (MTJs) and spin valves that are configured to operate based on spin-transfer torque switching.
Abstract:
A spin injection device and spin transistor including a spin injection device. A spin injection device includes different semiconductor materials and a spin-polarizing ferromagnetic material there between. The semiconductor materials may have different crystalline structures, e.g., a first material can be polycrystalline or amorphous silicon, and a second material can be single crystalline silicon. Charge carriers are spin-polarized when the traverse the spin-polarizing ferromagnetic material and injected into the second semiconductor material. A Schottky barrier height between the first semiconductor and ferromagnetic materials is larger than a second Schottky barrier height between the ferromagnetic and second semiconductor materials. A spin injection device may be a source of a spin field effect transistor.
Abstract:
Method of magnetization reversal of the magnetization (M) of at least one first magnetic memory element of an array of magnetic memory elements comprising the steps of: applying a first magnetic field pulse to a first set of magnetic memory ele-ments, and applying a second magnetic field pulse to a second set of magnetic memory elements, such that during the application of the first and second magnetic field pulse the magnetization (M) of said first magnetic memory element which is to be re-versed upon the field pulse decay performs approximately an odd number of a half precessional turns, wherein the magnetization (M) of at least one second magnetic memory element which is not to be reversed upon the field pulse de-cay performs approximately a number of full precessional turns. The underlying concept of the invention is to improve the bit addressing in an array of magnetic memory cells by reducing the ringing of the magnetization of the free layer of the magnetic cells which are not selected for reversal but which are nevertheless subject to the application of a magnetic field pulse. This can be achieved by applying a field pulse to these cells which induces approximately a full precessional turn of the magnetization of the free layer of the cells. After the full precessional turn the magnetization is oriented very near the initial orientation along the easy axis of magnetization and the magnetic ringing after application of the half select field pulse is reduced.