Nec Corporation

Tohoku University

Kyoto University

National Institutes for Quantum Science and Technology

Shunsuke Fukami

Nobuyuki Ishiwata

Tetsuhiro Suzuki

Kiyokazu Nagahara

Norikazu Ohshima

Hideo Ohno

Tetsuo Endoh

Hideo Sato

Shoji Ikeda

Fumihiro Matsukura

Michihiko Yamanouchi

Tadahiko Sugibayashi

Kyota Watanabe

Shinya Ishikawa

Hiroaki Honjo

Kenchi Ito

Masaaki Niwa

Mathias Bersweiler

William Andrew Borders

Kaoru Mori

Noboru Sakimura

Ryusuke Nebashi

Naoki Kasai

Hideaki Numata

Hironobu Tanigawa

Eiji Kariyada

Sadahiko Miura

Shigemi Mizukami

Shun Kanai

Yoshiro Hirayama

Seiji Sakai

Norikazu Oshima

Chaoliang Zhang

Toru Iwabuchi

Aleksandr Kurenkov

Yoshihisa Horikawa

Ayato Ohkawara

Satoshi Iihama

Junsaku Nitta

Keisuke Hayakawa

Takuya Funatsu

Chaoling Zhang

Tetsuro Anekawa

Daichi Chiba

A random number generation unit and a computing system using the same, the unit including a magnetic tunnel junction element and being capable of developing the characteristics required for the execution of probabilistic computing and operating at a higher speed. A magnetic tunnel junction element includes a fixed layer having a ferromagnet and having a magnetization direction fixed substantially, a free layer having a ferromagnet and having a magnetization direction varying with a first time constant, and a barrier layer disposed between the layers configured with an insulator. The magnetic tunnel junction element has a shift magnetic field of an absolute value of 20 millitesla or smaller. The fixed layer has a plurality of ferromagnetic and non-magnetic coupling layers laminated one upon another, and ferromagnetic layers adjacent to each other among the respective ferromagnetic layers are coupled in terms of magnetization by the non-magnetic coupling layers in an antiparallel manner.

Random number generation unit and computing system

A magneto-optical memory interface includes: a memory cell structure having multiple allocated magnetic recording cells, a selection means configured to select an individual or a predetermined number of the multiple allocated magnetic recording cells of the memory structure, and configured for an electronic signal to be applicable thereto; and a light irradiation part configured to irradiate the predetermined number of the multiple allocated magnetic memory cells with an optical signal, wherein each of the magnetic recording cells is a magnetic recording cell whose sensitivity to changes in a magnetization state thereof increases in response to an irradiation light from the light irradiation part, and each of the magnetic recording cells is a magnetic recording cell whose magnetization state changes in response to an applied electrical signal resulting from selection by the selection means and the irradiation light from the light irradiation part.

Magneto-optical memory interface

Provided is an X-type 3-terminal STT-MRAM (spin orbital torque magnetization reversal component) having a high thermal stability index &#x394; and a low writing current Iin a balanced manner. A magnetoresistance effect element has a configuration of channel layer ()/barrier layer non adjacent magnetic layer ()/barrier layer adjacent magnetic layer ()/barrier layer ().

Magnetoresistance effect element and magnetic memory

A magnetic tunnel junction element () includes a configuration in which a reference layer () that includes a ferromagnetic material, a barrier layer () that includes O, a recording layer () that includes a ferromagnetic material including Co or Fe, a first protective layer () that includes O, and a second protective layer () that includes at least one of Pt, Ru, Co, Fe, CoB, FeB, or CoFeB are layered.

Magnetic tunnel junction element and magnetic memory

There is provided a magnetoresistance effect element includes: a channel layer that extends in a first direction; a recording layer which includes a film formed from a ferromagnetic material, of which a magnetization state is changed to one of two or greater magnetization states, and which is formed on the channel layer; a non-magnetic layer that is provided on a surface of the recording layer; a reference layer which is provided on a surface of the non-magnetic layer, which includes a film formed from a ferromagnetic material, and of which a magnetization direction is fixed; a terminal pair that includes a first terminal and a second terminal which are electrically connected to the channel layer with an interval in the first direction, and to which a current pulse for bringing the recording layer to any one magnetization state with a plurality of pulses is input by flowing a current to the channel layer between the first terminal and the second terminal; and a third terminal that is electrically connected to the reference layer.

Magnetoresistance effect element, circuit device, and circuit unit

The magnetic memory element () includes: a conductive layer that includes a heavy metal layer () containing a 5d transition metal; a first ferromagnetic layer () that is adjacent to the conductive layer and contains a ferromagnetic layer having a reversible magnetization; a barrier layer () that is adjacent to the first ferromagnetic layer () and includes an insulating material; a reference layer () that is adjacent to the barrier layer () and has at least one second ferromagnetic layer () having a fixed magnetization direction; a cap layer () that is adjacent to the reference layer () and includes a conductive material; a first terminal (T) that is capable of introducing a current into one end of the heavy metal layer () in the longitudinal direction; a second terminal (T) that is capable of introducing a current into the other end of the heavy metal layer () in the longitudinal direction; and a third terminal (T) that is capable of introducing a current into the cap layer ().

Magnetic multilayer film, magnetic memory element, magnetic memory and method for producing same

A magnetoresistance effect element is provided, which can, even in a region where the element size of the magnetoresistance effect element is small, implement stable record holding at higher temperatures, and moreover which has higher thermal stability. The magnetoresistance effect element has a configuration including reference layer (B)/first non-magnetic layer ()/first magnetic layer ()/first non-magnetic insertion layer ()/second magnetic layer (). A magnetostatic coupling is established between the first magnetic layer () and the second magnetic layer () due to magnetostatic interaction becoming dominant.

Magnetoresistive element and magnetic memory

A magnetic material includes a structure in which a first magnetic layerand a second magnetic layerare stacked such that each layer is formed at least partially in a stacking direction by substantially one atomic layer. The first magnetic layer contains Co as a principal component. The second magnetic layer includes at least Ni. The magnetic material has magnetic anisotropy in the stacking direction. Preferably, an atomic arrangement within a film surface of the first magnetic layer and the second magnetic layer has six-fold symmetry.

Magnetic material and method of manufacturing the same

A magnetoresistance effect element includes first and second magnetic layers having a perpendicular magnetization direction, and a first non-magnetic layer disposed adjacent to the first magnetic layer and on a side opposite to a side on which the second magnetic layer is disposed. An interfacial perpendicular magnetic anisotropy exists at an interface between the first magnetic layer and the first non-magnetic layer, and the anisotropy causes the first magnetic layer to have a magnetization direction perpendicular to the surface of the layers. An atomic fraction of all magnetic elements to all magnetic and non-magnetic elements included in the second magnetic layer is smaller than that of the first magnetic layer.

A magnetoresistance effect element includes a bias layer comprised of an antiferromagnetic material and having a shape in which a first length in a first direction greater than a second length in a second direction perpendicular to the first direction, a recording layer comprised of a ferromagnetic material and being disposed on the bias layer, a direction of magnetization of the recording layer being reversible, a barrier layer comprised of an insulation material and being disposed on the recording layer, and a reference layer comprised of a ferromagnetic material and being disposed on the barrier layer, a direction of magnetization of the reference layer being substantially fixed.

Magnetoresistance effect element including a recording layer with perpendicular anisotropy and a bias layer comprised of an antiferromagnetic material, magnetic memory device, manufacturing method, operation method, and integrated circuit

A magnetoresistance effect element includes a recording layer containing a ferromagnetic body, and including a first fixed and second magnetization regions having magnetization components fixed substantially in a direction antiparallel to the in-plane direction to each other, and a free magnetization region disposed between the first and second fixed magnetization regions and having a magnetization component invertible in the in-plane direction, a domain wall disposed between the first fixed magnetization region and the free magnetization region, and being movable within the free magnetization region, and a magnetic nanowire having a width of 40 nm or less. The thickness of the recording layer is 40 nm or less and at least half but no more than twofold the width of the magnetic nanowire. The element further includes a barrier layer disposed on the recording layer, and a reference layer disposed on the barrier layer and containing a ferromagnetic body.

Magnetoresistance effect element and magnetic memory device

A magnetoresistance effect element includes a reference layer made of a ferromagnetic material, a recording layer made of a ferromagnetic material, and a barrier layer disposed between the reference layer and the recording layer. The reference layer and the recording layer have an in-plane magnetization direction parallel to a surface of the layers. The recording layer has a shape that has short axis and long axis perpendicular to the short axis in plan view. A first value obtained by dividing a thickness of the recording layer by a length of the short axis of the recording layer is greater than 0.3 and smaller than 1.

A magnetoresistance effect element includes first and second magnetic layers having a perpendicular magnetization direction, and a first non-magnetic layer disposed adjacent to the first magnetic layer and on a side opposite to a side on which the second magnetic layer is disposed. An interfacial perpendicular magnetic anisotropy exists at an interface between the first magnetic layer and the first non-magnetic layer, and the anisotropy causes the first magnetic layer to have a magnetization direction perpendicular to the surface if the layers. The second magnetic layer has a saturation magnetization lower than that of the first magnetic layer, and an interfacial magnetic anisotropy energy density (K) at the interface between the first magnetic layer and the first non-magnetic layer is greater than that of an interface between the first non-magnetic layer and second magnetic layers if being disposed adjacent each other.

A magnetoresistive device includes a magnetic free layer having first and second surfaces, the magnetic free layer being comprised of a ferromagnetic material having a perpendicular magnetic anisotropy, a spin current generation layer contacting the first surface of the magnetic free layer, a tunnel barrier layer having one surface contacting the second surface of the magnetic free layer, a reference layer contacting another surface of the tunnel barrier layer, and a leakage field generation layer including first and second leakage field generation layers each of which is comprised of a ferromagnetic material and generates a leakage field, an in-plane component of the leakage field at an part of the magnetic free layer is formed generating a domain wall having an in-plane magnetization component in the magnetic free layer.

Three terminal magnetoresistive devices, magnetoresistive random access memory and magnetic recording method

A magnetoresistance effect element () includes a heavy metal layer () that includes a heavy metal and that is formed to extend in a first direction, a recording layer () that includes a ferromagnetic material and that is provided adjacent to the heavy metal layer (), a barrier layer () that includes an insulating material and that is provided on the recording layer () with being adjacent to a surface of the recording layer () opposite to the heavy metal layer (), and a reference layer () that includes a ferromagnetic material and that is provided adjacent to a surface of the barrier layer (), the surface being opposite to the recording layer (). The direction of the magnetization of the reference layer () has a component substantially fixed in the first direction, and the direction of the magnetization of the recording layer () has a component variable in the first direction. A current having a direction same as the first direction is introduced to the heavy metal layer () to thereby enable the magnetization of the recording layer () to be inverted.

Growing community of inventors

Tokyo, Japan

Shunsuke Fukami