Fujitsu

An information processing apparatus acquires measurement data indicating measurement values of quantum states of qubits measured after a quantum computer has repeatedly executed, a plurality of times, a quantum gate sequence including a plurality of quantum gates for the qubits. The information processing apparatus divides a space to which a matrix indicating a quantum operation by the quantum gate sequence belongs into a first subspace including a singular point at which eigenvalues satisfying predetermined conditions are calculated, and a second subspace that does not include the singular point, and generates, within a range of the second subspace, a function that linearly approximates an influence of an error of a quantum gate included in the plurality of quantum gates on the measurement value. The information processing apparatus estimates, by using the function and the measurement data, the error of the quantum gate when the quantum computer executes the quantum gate.

A processing unit groups a plurality of sequences to be aligned in a multiple sequence alignment problem into a plurality of groups, selects a representative sequence from each of the plurality of groups, and causes an Ising machine to perform a first alignment process among the representative sequences of the plurality of groups. The processing unit replaces the representative sequence before the first alignment process with the corresponding representative sequence obtained through the first alignment process in each of the plurality of groups, and causes the Ising machine to perform a second alignment process within each of the plurality of groups after the replacement of the representative sequences.

An information processing program causes a computer to execute a process including detecting a bounding box of an object in a plurality of frames captured by a camera installed at a predetermined point, and generating a heat map that represents average reliability at each set of coordinates in a range captured by the camera, based on reliability of each of a plurality of the detected bounding boxes.

An information processing program for causing a computer to execute a process, the process includes: obtaining a decomposition number of a Trotter decomposition approximating a quantum unitary corresponding to an Ising model; and setting a quantum circuit expressing a formula of the Trotter decomposition by one or more first partial circuits and a second partial circuit, the one or more first partial circuits being of a first count one less than the obtained decomposition number and each including an Rz gate that represents a rotation action about a Z-axis on a qubit, the second partial circuit being free of the Rz gate and coupled to a rear of the one or more first partial circuits.

A quantum device (100) includes a quantum chip (10) including a substrate (11) having a first surface (12) and a second surface (13), a quantum bit (15) provided on the first surface, and an electrode (18) electrically connected to the quantum bit and provided on the second surface, a mounting portion (30) having a mounting surface (32) on which a peripheral edge portion of the quantum chip is mounted, the mounting portion having a linear expansion coefficient different from that of the substrate, a conductor pin (40) having a tip end in contact with the electrode, and a holding portion (50) fixed to the mounting portion, the holding portion holding the conductor pin and having a linear expansion coefficient different from that of the substrate, wherein the electrode has a shape having a longitudinal direction in a direction radially extending from a center of the substrate in plan view, and the quantum chip is mounted on the mounting surface by inserting a protrusion (31) provided on one of the substrate and the mounting surface into a hole (19) provided on another of the substrate and the mounting surface, the hole having a longitudinal direction in a direction extending radially in plan view.

A processing unit acquires the data of first and second classical shadows corresponding to first and second quantum data represented by qubits, and geometric structure information indicating the geometric structure of a space including lattice points associated with the qubits. The first and second classical shadows include first and second data elements, respectively, corresponding to the qubits. The processing unit sets local subspaces each including a set of local lattice points in the space, based on the geometric structure information. The processing unit calculates, for each local subspace, a value of a first kernel function based on first and second data elements of the first and second classical shadows corresponding to the lattice points of that local subspace, and calculates a value of a second kernel function corresponding to the first and second classical shadows, based on the values of the first kernel function corresponding to the local subspaces.

An information processing program for causing a computer to execute a process including: setting first and second functions, for a quantum circuit used when solving a combinatorial optimization problem and including, for each layer, a first partial circuit representing an action of a mixer unitary operator and a second partial circuit representing an action of a cost unitary operator, the first function representing a first variational parameter of the first partial circuit, the second function representing a second variational parameter of the second partial circuit; and calculating a solution to the combinatorial optimization problem by updating a value of a first transformation parameter related to the first function and a value of a second transformation parameter related to the second function so as to optimize an expected value of a cost function corresponding to the combinatorial optimization problem by using the quantum circuit after setting the first function and the second function.

A method of manufacturing a Josephson junction element includes forming a lower electrode (20) on a substrate (10) by using a superconducting material, depositing a first insulating film (30) on the substrate to cover the lower electrode, depositing a superconducting film on the first insulating film, and forming an upper electrode (40) by etching the superconducting film, the upper electrode covering an entire lower electrode in plan view and having an outer peripheral edge located outside an outer peripheral edge of the lower electrode.

A quantum device includes a first qubit circuit, a second qubit circuit, and a cover chip. The first qubit circuit includes a first port, a first qubit, and a first resonator coupled to the first qubit and the first port and having a first resonant frequency. The second qubit circuit includes a second port, a second qubit, and a second resonator coupled to the second qubit and the second port and having a second resonant frequency different from the first resonant frequency. The cover chip includes a waveguide coupled to the first port and the second port.

A method of manufacturing a quantum device (100, 200) includes bonding a diamond substrate (30) including a color center (21) to a layer (32) provided on a support substrate (10), forming a first portion (40) including the color center, and a second portion (42) having an inclined surface (43) inclined with respect to a side wall (41) of the first portion by etching the diamond substrate after the bonding the diamond substrate, forming a metal film (45) on the inclined surface, and forming a first optical waveguide portion (20) by cutting the first portion at a first position farther from the layer than the color center by emitting a laser beam reflected by the metal film onto the side wall of the first portion.