Inter-University Research Institute Corporation Research Organization of Information and Systems

Nippon Telegraph and Telephone Corporation

Leland Stanford Junior University

Osaka University

Shoko Utsunomiya

Yoshihisa Yamamoto

Hiroki Takesue

Takahiro Inagaki

Toshimori Honjo

Kenta Takata

Shuhei Tamate

Robert L Byer

Kensuke Inaba

Alireza Marandi

Koji Igarashi

Zhe Wang

Kai Yan

Yoshitaka Haribara

Kai Wen

A calculation device of the present disclosure is characterized by implementing an item, which expresses a magnetic field, at each site by adding, to the conventional coherent Ising machine, a function for simulating the magnetic field item. Specifically, light having the amplitude of a predetermined sign is input in the conventional coherent Ising machine by dislocating an operation point of the push-pull-type optical modulator. When the operation point is dislocated to a + direction, DOPO (Degenerate Optical Parametric Oscillator) having the same wavelength as that of DOPO of an optical resonator and having a fixed initial phase difference from pump light into which the light is injected considerably tends to oscillate at 0 phase, and becomes reversed when the operation point is dislocated to a minus direction.

Computing device of Ising model

In an Ising spin measuring step, measurement is suspended after one set of measurement of all Ising spins {&#x3c3;} is completed before another set of measurement of all Ising spins {&#x3c3;} is restarted. In an Ising interaction computing step, all Ising interactions relating to all the Ising spins &#x3c3;can be computed with a sufficient time margin on the basis of most recent measurement of Ising spins &#x3c3;, after one set of measurement of all the Ising spins {&#x3c3;} is completed before another set of measurement of all the Ising spins {&#x3c3;} is restarted by the Ising spin measuring step.

Ising model quantum computation device

A parametric oscillator oscillates a plurality of pseudo spin pulses SPi having mutually an identical oscillation frequency by using parametric oscillation, an interaction implementing unit performs feedback implementation of a magnitude and a sign of interaction related to each pseudo spin pulse SPi (the proportionality coefficient &#x3bb;+&#x3a3;J&#x3c3;+&#x3a3;K&#x3c3;&#x3c3;with respect to &#x3c3;) by using a tentative measurement result of oscillation phases &#x3d5;(tentative) of the plurality of pseudo spin pulses SPi, and a pseudo spin measuring unit measures the pseudo spins &#x3c3;of the plurality of pseudo spin pulses SPi, based on a final measurement result of oscillation phases &#x3d5;(steady) of the plurality of pseudo spin pulses SPi.

Quantum computing device for Ising model, quantum parallel computing device for Ising model, and quantum computing method for Ising model

In one aspect, a computational machine includes an optical device configured to receive energy from an optical energy source and generate a number Nof optical signals, and a number Nof coupling devices, each of which controllably couples a plurality of the number Noptical signals. The coupling devices are individually controlled to simulate a computational problem. In another aspect, a computational machine includes a number Nof parametric oscillators and a number Nof coupling devices, each of which controllably couples a plurality of the number Nof parametric oscillators together. The coupling devices are individually controlled to simulate a computational problem.

Computation using a network of optical parametric oscillators

This computation device and method exponentially shortens a computation time of an NP-complete problem or the like mapped into an Ising model by exponentially shortening a computation time of the Ising mode. For each pair of a plurality of slave lasers, by controlling the intensity, the polarization, and the phase of light exchanged between two slave lasers using an attenuator and a wave plate, the magnitude and the sign of pseudo Ising interaction between two slave lasers are implemented. Then, after the plurality of slave lasers arrive at a steady state, by measuring the polarization of light generated by each slave laser with left-handed circular polarization and right-handed circular polarization used as bases, a pseudo spin of each slave laser is measured.

Ising model quantum computation device and Ising model quantum computation method

For each pair of a plurality of slave lasers B for which injection synchronization is performed by a master laser M, by controlling the intensity of light exchanged between two slave lasers B and an optical path length between the two slave lasers B using a slave-to-laser intensity control unit IA and an inter-slave laser optical path length control unit IP, the magnitude and the sign of pseudo ising interaction Jbetween the two slave lasers B are implemented. After the plurality of slave lasers B arrive at a steady state, by measuring relative values of the oscillation phases of the plurality of slave lasers B with respect to the oscillation phase of the master laser M by using an oscillation phase measuring unit PM, pseudo ising spins &#x3c3;of the plurality of slave lasers B are measured.

Quantum computer and quantum computing using ising model

Growing community of inventors

Tokyo, Japan

Shoko Utsunomiya