Kabushiki Kaisha Toshiba

Taro Kanao

Hayato Goto

Koichi Mizushima

Hirofumi Suto

Tazumi Nagasawa

Rie Sato

Kosuke Tatsumura

Kiwamu Kudo

Michinaga Yamagishi

Noritsugu Shiokawa

Tamio Kawaguchi

Ryo Hidaka

Yinghao Ho

An electronic circuit includes a band-pass filter, and at least one first circuit. The band-pass filter includes a plurality of filter resonators. Two adjacent filter resonators included in the filter resonators are mutually couplable. The first circuit includes a first qubit and a first readout resonator. The first readout resonator is couplable with the first qubit and one of the filter resonators. A passband of the band-pass filter includes a first passband and a second passband. A magnitude of a first ripple of the first passband is not more than 1/10 of a magnitude of a second ripple of the second passband.

Electronic circuit and calculator

According to one embodiment, a calculating device includes nonlinear oscillators, connectors, and a controller. One of the connectors connects at least two of the nonlinear oscillators. The nonlinear oscillators include first and second nonlinear oscillators. The first nonlinear oscillator includes a first circuit part and a first conductive member. The first circuit part includes first and second Josephson junctions. The second nonlinear oscillator includes a second circuit part and a second conductive member. The second circuit part includes third and fourth Josephson junctions. Numbers of the connectors connected to the first and second connectors are first and second numbers, respectively. The second number is greater than the first number. The controller performs at least a first operation of supplying a first signal to the first conductive member and supplying a second signal to the second conductive member. The second signal is different from the first signal.

Calculating device

A calculation device includes a memory and one or more processors coupled to the memory and configured to alternately update, for elements each associated with first and second variables, the first and second variables, sequentially for unit times from an initial time to an end time. In an updating process for each unit time, the one or more processors are configured to: update, for each of the elements, the first variable based on the second variable; when the first variable is smaller than a first value, change the first variable to the first value and change the second variable to a third value; when the first variable is greater than a second value, change the first variable to the second value and change the second variable to the third value; and add an acceleration value calculated by a predetermined computation to the second variable.

Calculation device, calculation method, and computer program product

According to one embodiment, a calculating device includes a processor repeating a processing procedure. The processing procedure includes first, second, and third variable updates. The first variable update includes updating an ith entry of a first variable xby adding an ith entry of a first function to the first variable x. The second variable update includes updating the second variable yby adding, to the second variable y, an arithmetic result of an ith entry of a second function, an ith entry of a third function, and an ith entry of a first element function. The third variable update includes updating the third variable z by adding an ith entry of a second element function to the third variable z. The processor performs at least an output of at least one of the first variable xor a function of the first variable x.

Calculating device, calculation program, recording medium, and calculation method

According to one embodiment, a calculating device includes a nonlinear oscillator. The nonlinear oscillator includes a circuit part including a first Josephson junction and a second Josephson junction, and a conductive member including a first terminal. An electrical signal is input to the first terminal. The electrical signal includes a first signal in a first operation. The first signal includes a first frequency component having a first frequency, and a second frequency component having a second frequency. The first frequency is 2 times an oscillation frequency of the nonlinear oscillator. An absolute value of a difference between the first frequency and the second frequency is not more than 0.3 times the first frequency.

A calculation apparatus according to an embodiment includes one or more processing circuits configured to function as an interaction unit, a first addition unit, and a time evolution unit. The interaction unit generates N first intermediate variables obtained by performing a matrix computing on the N first variables and the coefficient matrix at the first time. The first addition unit calculates N second variables at the second time at which the sampling period elapses from the first time. The time evolution unit executes a time evolution process on the N second variables at the first time to generate N first variables at the second time. If the N first variables at the second time unsatisfied a predetermined constraint condition, the time evolution unit changes the N second variables at the second time in a direction of satisfying the constraint condition.

Calculation apparatus, calculation method and computer program product

According to one embodiment, a calculating device includes a processor. The processor acquires a data set {s} and repeats a processing procedure. The processing procedure includes first and second variable updates. The first variable update includes updating an ith entry of a first variable xby adding a first function to the ith entry of the first variable x. The ith entry of the first variable xis one of a first variable set {x}. A variable of the first function includes at least a part of a second variable set {y}. The second variable update includes updating an ith entry of a second variable yby adding a second function and a third function to the ith entry of the second variable y. The ith entry of the second variable yis one of the second variable set {y}. The processor outputs at least a fourth function.

According to one embodiment, a calculating device includes a processor repeating a processing procedure. The processing procedure includes a first variable update and a second variable update. The first variable update includes updating a first variable xby adding a first function to the first variable xbefore the first variable update. The second variable update includes updating the second variable yby adding a second function and a third function to the second variable ybefore the second variable update. A variable of the first function set includes a calculation parameter. The calculation parameter is different before and after the processing procedure. The processor performs at least an output of at least one of the first variable xobtained after the repeating of the processing procedure or a function of the first variable xobtained after the repeating of the processing procedure.

According to one embodiment, an oscillator includes a first element. The first element includes first and second magnetic layers, and a first nonmagnetic layer. The first magnetic layer includes first and second magnetic films, and a first nonmagnetic film. The second magnetic film is provided between the second magnetic layer and the first magnetic film. The first nonmagnetic layer is provided between the second magnetic film and the second magnetic layer. An orientation of a first magnetization of the first magnetic film has a reverse component of an orientation of a second magnetization of the second magnetic film. A first magnetic field is applied to the first element. The first element is in a first state when a first current flows in the first element. An electrical resistance of the first element in the first state includes first and second electrical resistances repeating alternately.

Oscillator and calculating device

According to one embodiment, a magnetic head includes a first magnetic layer, a second magnetic layer, an intermediate layer, a magnetic pole, a first terminal, and a second terminal. The second magnetic layer is separated from the first magnetic layer in a first direction. The intermediate layer is provided between the first magnetic layer and the second magnetic layer. A second direction from the first magnetic layer toward the magnetic pole crosses the first direction. The first terminal is electrically connected to the intermediate layer. The second terminal is electrically connected to the second magnetic layer.

Magnetic head with spin torque oscillator connection configuration

According to one embodiment, a magnetic recording medium includes a first layer and a second layer. The first layer includes a first magnetic region, a second magnetic region, and a nonmagnetic region provided between the first and second magnetic regions. A direction from the second magnetic region toward the first magnetic region is along a first direction. The second layer includes third, fourth, and fifth magnetic regions. At least a portion of the fifth magnetic region is provided between the third and fourth magnetic regions. The third magnetic region overlaps the first magnetic region in a second direction crossing the first direction. The fourth magnetic region overlaps the second magnetic region in the second direction. The fifth magnetic region overlaps the nonmagnetic region in the second direction. An easy magnetization axis of each of the first to fifth magnetic regions is aligned with the second direction.

Magnetic recording medium including multiple magnetic layers with multiple regions having aligned easy magnetization axes and magnetic recording and reproducing device

According to one embodiment, a magnetic recording and reproducing device includes a magnetic recording medium, a magnetic head, and a controller. The controller implements a first operation and a second operation. The first operation is implemented in a first information recording interval including a first recording interval and a first non-recording interval. The second operation is implemented in a second information recording interval including a second recording interval and a second non-recording interval. The first operation includes in the first recording interval, generating a first signal magnetic field from the magnetic head, and in the first non-recording interval, generating a first non-signal magnetic field from the magnetic head. The second operation includes in the second recording interval, generating a second signal magnetic field from the magnetic head, and in the second non-recording interval, generating a second non-signal magnetic field from the magnetic head.

Perpendicular magnetic recording and reproducing device

According to an embodiment, a computing apparatus includes spin torque oscillators, an interaction unit, a variable direct-current supply device, and a measuring unit. The interaction unit controls an interaction between the spin torque oscillators. The variable direct-current supply device supplies a current to induce oscillations of the spin torque oscillators. The measuring unit measures AC signals obtained from the spin torque oscillators.

Computing apparatus and computing method

A magnetic recording and reproducing apparatus for recording and reproducing bit information comprising a magnetic head having a spin torque oscillator configured to readout bit information which is recorded on a magnetic recording medium, a detector configured to detect amplitude of a first signal, the first signal which is to reproduce the bit information, and a controller configured to control the magnetic head so as to read the bit information recorded on the magnetic recording medium when the amplitude of the first signal detected by the detector is smaller than a predetermined value.

Magnetic recording and reproducing apparatus and magnetic recording and reproducing method

According to one embodiment, a magnetic recording and reproducing device includes a magnetic recording medium, and a magnetic head including a first reproducing unit. The first reproducing unit includes a first magnetic field generator separated from the magnetic recording medium in a first direction, and a first stacked body. At least a portion of the first stacked body is provided between the magnetic recording medium and the first magnetic field generator in the first direction. The first stacked body includes a first magnetic layer, a second magnetic layer separated from the first magnetic layer in a second direction crossing the first direction, and a first intermediate layer provided between the first magnetic layer and the second magnetic layer. The first stacked body performs an operation of generating a first alternating magnetic field. The first magnetic field generator generates a first magnetic field.

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Kanagawa, Japan

Taro Kanao