New York University

Raytheon Bbn Technologies Corp.

University of Iowa Research Foundation

Bar-ilan University

Andrew David Kent

Huanlong Liu

Daniel Bedau

Daniel L Stein

Jean-Marc Beaujour

Enrique Gonzalez Garcia

Barbaros Özyilmaz

Frank C Hoppensteadt

Dirk Backes

Barbaros Ozyilmaz

Thomas Ohki

Michael Flatté

Lior Klein

Mordechai Schultz

Markus Wohlgenannt

Fujian Wang

Thomas Akira Okhi

Nicholas Harmon

Ferran Macia Bros

Ferran Macià Bros

Yevgeniy Telepinsky

Yu-Ming Hung

A multi-state MRAM device comprises N overlapping ovals defining a free ferromagnetic region. The size of the free ferromagnetic region is controlled the shape anisotropy of the configuration via at least a aspect ratio greater than 2, of the free ferromagnetic region. The free ferromagnetic region has a magnetic moment spontaneously aligned along the long axis in each oval outside the center region. A center magnetic moment has a multitude of exactly 2*N stable orientations determined by the magnetic moments in the segments of the ovals outside the center region. An embodiment is an MRAM device using tunneling junctions to achieve a multi-state memory configuration. Certain embodiments includes an electrically conducting heavy-metal layer disposed adjacent to and connected with the free ferromagnetic region. Some embodiments include a topological insulating material, such as BiSe. Magnetic moment reversal in the ovals may be determined by spin-transfer torque associated with the electrically conducting layer.

Multi-state magnetic memory device

An optoelectronic device which can read magnetically stored information, and convert it into optical light signals using organic or 'plastic' semiconductors is described. Such a device may use OLEDs, and may be termed an 'organic magneto-optic transducer' (OMOT). An OMOT device can read magnetically stored information, and convert it into optical light signals. The OMOT may provide benefits such as non-volatile storage, flexible films, reduced cost, and operation at room temperature.

Organic magnetoelectroluminescence for transduction between magnetic and optical information

A high speed, low power method to control and switch the magnetization direction of a magnetic region in a magnetic device for memory cells using spin polarized electrical current. The magnetic device comprises a pinned magnetic layer, a reference magnetic layer with a fixed magnetization direction and a free magnetic layer with a changeable magnetization direction. The magnetic layers are separated by insulating non-magnetic layers. A current can be applied to the device to induce a torque that alters the magnetic state of the device so that it can act as a magnetic memory for writing information. The resistance, which depends on the magnetic state of the device, can be measured to read out the information stored in the device.

Current induced spin-momentum transfer stack with dual insulating layers

A magnetic device includes a pinned polarizing magnetic layer having a magnetic vector parallel to a plane of the pinned polarizing magnetic layer. The magnetic device also includes a free layer, separated from the polarizing magnetic layer by a first non-magnetic layer, having a magnetization vector with a changeable magnetization direction. The changeable magnetization vector is configured to change to a first state upon application of a first current of a first polarity and to change to a second state upon application of a second current of a second, opposite polarity. The magnetic device also has a reference layer having a magnetic vector perpendicular to the plane of the reference layer and separated from the free layer by a second non-magnetic layer.

Scalable orthogonal spin transfer magnetic random access memory devices with reduced write error rates

A nano-oscillator magnetic wave propagation system has a group of aggregated spin-torque nano-oscillators (ASTNOs), which share a magnetic propagation material. Each of the group of ASTNOs is disposed about an emanating point in the magnetic propagation material. During a non-wave propagation state of the nano-oscillator magnetic wave propagation system, the magnetic propagation material receives a polarizing magnetic field. During a wave propagation state of the nano-oscillator magnetic wave propagation system, each of the group of ASTNOs initiates spin waves through the magnetic propagation material, such that a portion of the spin waves initiated from each of the group of ASTNOs combine to produce an aggregation of spin waves emanating from the emanating point. The aggregation of spin waves may provide a sharper wave front than wave fronts of the individual spin waves initiated from each of the group of ASTNOs.

Aggregated spin-torque nano-oscillators

A magnetic device that includes a perpendicular magnetized polarizing layer configured to provide a first spin-torque and an in-plane magnetized free layer having a magnetization vector having at least a first stable state and a second stable state. The magnetic device also includes a reference layer configured to provide a second spin-torque. The first spin-torque and the second spin-torque can combine. The in-plane magnetized free layer and the reference layer form a magnetic tunnel junction and the combined first spin-torque and second spin-torque influences the magnetic state of the in-plane magnetized free layer. An application of a voltage pulse, having either positive or negative polarity and a selected amplitude and duration, through the magnetic device causes the magnetization vector to oscillate between the first stable state and the second stable state for a portion of the duration regardless of an initial state of the magnetization vector.

Precessional magnetization reversal in a magnetic tunnel junction with a perpendicular polarizer

A magnetic memory system includes a superconductor circuit and one or more magnetic memory elements to store data. To write data, a driver circuit in the superconductor circuit generates a magnetic signal for transmission over a superconductor link extending between the superconductor circuit and the magnetic memory element. To read data, a sensing circuit in the superconductor circuit monitors a superconductor link extending from sensing circuit to the magnetic memory element. The magnetic memory element can be a spin-transfer type magnetic memory element.

Magnetic memory system and methods in various modes of operation

A magnetic device includes a magnetized polarizing layer, a free magnetic layer, and a reference layer. The free magnetic layer forms a first electrode and is separated from the magnetized polarizing layer by a first non-magnetic metal layer. The free magnetic layer has a magnetization vector having a first and second stable state. The reference layer forms a second electrode and is separated from the free-magnetic layer by a second non-magnetic layer. Unipolar current is sourced through the polarizing, free magnetic and reference layers. Switching of the magnetization vector of the free magnetic layer from the first stable state to the second state is initiated by application of a first unipolar current pulse, and switching of the magnetization vector of the free magnetic layer from the second stable state to the first stable state is initiated by application of a second unipolar current pulse.

Bipolar spin-transfer switching

A magnetic device includes a pinned magnetic layer and a free magnetic layer including a first body-centered cubic material and having a variable magnetization vector that has a first stable state and a second stable state. The magnetic device also includes a first non-magnetic layer and a reference layer. The first non-magnetic layer spatially separates the pinned magnetic layer and the free magnetic layer and includes a second body-centered cubic material that interfaces with the first body-centered cubic material. The magnetic device includes a second non-magnetic layer spatially separating the free magnetic layer and the reference magnetic layer. A magnetic tunnel junction, located below the pinned magnetic layer, is formed by the free magnetic layer, the second non-magnetic layer, and the reference magnetic layer. Application of a current pulse through the magnetic device switches the variable magnetization vector.

Increased magnetoresistance in an inverted orthogonal spin transfer layer stack

A magnetic device includes a pinned magnetic layer having a first fixed magnetization vector with a first fixed magnetization direction. The magnetic device also includes a free magnetic layer having a variable magnetization vector having at least a first stable state and a second stable state. The magnetic device also has a first non-magnetic layer and a reference. The first non-magnetic layer spatially separates the pinned magnetic layer and the free magnetic layer. The magnetic device also includes a second non-magnetic layer spatially separating the free magnetic layer and the reference magnetic layer. A magnetic tunnel junction, located below the pinned magnetic layer, is formed by the free magnetic layer, the second non-magnetic layer, and the reference magnetic layer. Application of a current pulse, having either positive or negative polarity and a selected amplitude and duration, through the magnetic device switches the variable magnetization vector.

Inverted orthogonal spin transfer layer stack

Orthogonal spin-torque bit cells whose spin torques from a perpendicular polarizer and an in-plane magnetized reference layer are constructively or destructively combined. An orthogonal spin-torque bit cell includes a perpendicular magnetized polarizing layer configured to provide a first spin-torque; an in-plane magnetized free layer and a reference layer configured to provide a second spin-torque. The first spin-torque and the second spin-torque combine and the combined first spin-torque and second spin-torque influences the magnetic state of the in-plane magnetized free layer. The in-plane magnetized free layer and the reference layer form a magnetic tunnel junction. The first spin-torque and second spin-torque can combine constructively to lower a switching current, increase a switching speed, and/or torque decrease an operating energy of the orthogonal spin-torque bit cell.

Precessional reversal in orthogonal spin transfer magnetic RAM devices

A high speed, low power method to control and switch the magnetization direction and/or helicity of a magnetic region in a magnetic device for memory cells using spin polarized electrical current. The magnetic device comprises a reference magnetic layer with a fixed magnetic helicity and/or magnetization direction and a free magnetic layer with a changeable magnetic helicity and/or magnetization direction. The fixed magnetic layer and the free magnetic layer are preferably separated by a non-magnetic layer. The fixed and free magnetic layers may have magnetization directions at a substantially non-zero angle relative to the layer normal. A current can be applied to the device to induce a torque that alters the magnetic state of the device so that it can act as a magnetic memory for writing information. The resistance, which depends on the magnetic state of the device, is measured to read out the information stored in the device.

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New York, NY, United States of America

Andrew David Kent