Provided are a method for coupling any two qubits from among multiple superconducting qubits and a system thereof, which are applied to an occasion provided with a multi-superconducting-qubit array and a magnetic film material capable of implementing spin waves. The method includes: disposing a magnetic film material below a multi-superconducting-qubit array; forming, through a combination of magnetization directions of magnetic domains in the magnetic film material, multiple channels through which the spin waves pass; disposing multiple qubits of the multi-superconducting-qubit array above the multiple channels through which the spin waves pass correspondingly to implement a coupling between each qubit and the spin waves; and disposing at least two qubits above one spin wave channel and implementing a coupling between the at least two qubits through the coupling between each qubit and the spin waves.

A method is described for controlling a spin qubit quantum device that includes a semiconducting portion, a dielectric layer covered by the semiconducting portion, a front gate partially covering an upper edge of the semiconducting portion, and a back gate. The method includes, during a manipulation of a spin state, the exposure of the device to a magnetic field B of value such that g.Math..sub.B.Math.B>min((Vbg)). The method also includes the application, on the rear gate, of an electrical potential Vbg of value such that (Vbg)<g.Math..sub.B.Math.B+2|M.sub.SO|, and the application, on the front gate, of a confinement potential and an RF electrical signal triggering a change of spin state, with g corresponding to the Land factor, .sub.B corresponding to a Bohr magneton, corresponding to an intervalley energy difference in the semiconducting portion, and M.sub.SO corresponding to the intervalley spin-orbit coupling.

In order to provide a memory element configured to generate and detect monopole current, in an embodiment provided in the present disclosure is a monopole current generation detection device comprising a ferromagnetic quantum spin-ice layer, a buffer layer made of a material capable of exhibiting a quantum spin-liquid state, and a pair of electrodes disposed in contact with the buffer layer. In this device it is possible to apply a voltage between the pair of electrodes by providing a voltage application means. It is possible to generate a monopole current J.sup.m upon application of the voltage, where the monopole currents through the ferromagnetic quantum spin-ice layer and through another ferromagnetic quantum spin-ice layer that is in contact with the buffer layer on the other side of the ferromagnetic quantum spin-ice layer. Also, the monopole current can be electrically detected by providing a detection circuit to the device. In embodiments of the present disclosure, further provided is a memory element in which a buffer layer is sandwiched by two ferromagnetic quantum spin-ice layers.

An apparatus is provided which comprises: a first magnet with perpendicular magnetic anisotropy (PMA); a stack of layers, a portion of which is adjacent to the first magnet, wherein the stack of layers is to provide an inverse Rashba-Bychkov effect; a second magnet with PMA; a magnetoelectric layer adjacent to the second magnet; and a conductor coupled to at least a portion of the stack of layers and the magnetoelectric layer.

Described is an apparatus which comprises: an input ferromagnet to receive a first charge current and to produce a first spin current; a first layer configured to convert the first spin current to a second charge current via spin orbit coupling (SOC), wherein at least a part of the first layer is coupled to the input ferromagnet; and a second layer configured to convert the second charge current to a second spin current via spin orbit coupling (SOC).

A magnetically polarized photonic device is provided. The magnetically polarized photonic device (100) includes substrate (102), an annihilation layer (106) and a graded band gap layer (142). The annihilation layer (106) is deposed on a surface (104) of substrate (102) with graded band gap layer (142) disposed on annihilation layer (106). Contacts (116, 128) are disposed on ends (146, 150) of magnetically polarized photonic device (100). A magnetic field (159) is applied to graded band gap layer (142) and annihilation layer (106) to drive charges to contacts (116, 128).

A base element for switching a magnetization state of a nanomagnet includes a heavy-metal nanostrip having a surface. A ferromagnetic nanomagnet is disposed adjacent to the surface. The ferromagnetic nanomagnet includes a shape having a long axis and a short axis. The ferromagnetic nanomagnet has both a perpendicular-to-the-plane anisotropy H.sub.kz and an in-plane anisotropy H.sub.kx and the ferromagnetic nanomagnet has a first magnetization equilibrium state and a second magnetization equilibrium state. The first magnetization equilibrium state or the second magnetization equilibrium state is settable by a flow of electrical charge through the heavy-metal nanostrip. A direction of flow of the electrical charge through the heavy-metal nanostrip includes an angle with respect to the short axis of the nanomagnet.

A magnetic sensor, comprising: a substrate having a groove; two conductive magnetic wires for magnetic field detection arranged adjacent and substantially parallel to one another and at least partially recessed in the groove on the substrate, the two conductive magnetic wires electrically coupled at one end; a coil surrounding the two magnetic wires; two electrodes coupled to the two conductive magnetic wires for wire energization; and two electrodes coupled to the coil for coil voltage detection.

The present disclosure provides a skyrmion diode using skyrmions as information carriers. The skyrmion diode includes a magnetic body and a conductive body. The magnetic body has a skyrmion which is used as information carrier. The conductive body is disposed on or under the magnetic body. The conductive body includes a Dzyaloshinskii-Moriya interaction (DMI) region and a defect region. The DMI region is provided to induce DMI in a region of the magnetic body corresponding to the DMI region by the spin-orbit coupling of the conductive body and magnetic moments of the magnetic body. The defect region is provided to prevent the DMI from being induced in a region of the magnetic body corresponding to the defect region.

The various implementations described herein include magnetic memory devices and systems, and methods for injecting defects into the devices and systems. In one aspect, a magnetic memory device comprises a non-magnetic cylindrical core, a first portion, and a second portion. The core is configured to receive a current. The first portion surrounds the core and is configured to introduce magnetic instabilities into the second portion. The second portion is adjacent to and arranged in a stack with respect to the first portion. The second portion also surrounds the core and is configured to store information based on a respective position of the magnetic instabilities. The second portion comprises a first plurality of magnetic layers and a first plurality of non-magnetic layers. Respective magnetic layers of the first plurality of magnetic layers are separated by respective non-magnetic layers of the plurality of non-magnetic layers.