Abstract: Systems and methods for composite quantum gate calibration for a quantum computing system are provided. In some implementations, a method includes accessing a unitary gate model describing a composite quantum gate. The unitary gate model includes a plurality of gate parameters. The method includes implementing the composite quantum gate for a plurality of gate cycles on the quantum system to amplify the plurality of gate parameters. The method includes obtaining a measurement of a state of the quantum system after implementing the composite quantum gate for the plurality of gate cycles. The method includes determining at least one of the plurality of gate parameters based at least in part on the measurement of the state of the quantum system. The method includes calibrating the composite quantum gate for the quantum computing system based at least in part on the plurality of gate parameters.

Abstract: Methods, devices, and systems are described for performing quantum operations. An example device at least one magnetic field source configured to supply an inhomogeneous magnetic field, at least one semiconducting layer, and one or more conducting layers configured to: define at least two quantum states in the at least one semiconducting layer, and cause, based on an oscillating electrical signal supplied by the one or more conducting layers, an electron to move back and forth between the at least two quantum states in the presence of the inhomogeneous magnetic field. The movement of the electron between the at least two quantum states may generate an oscillating magnetic field to drive a quantum transition between a spin-up state and spin-down state of the electron thereby implementing a qubit gate on a spin state of the electron.

Abstract: Methods, devices, and systems are described for storing and transferring quantum information. An example device may comprise at least one semiconducting layer, one or more conducting layers configured to define at least two quantum states in the at least one semiconducting layer and confine an electron in or more of the at least two quantum states, and a magnetic field source configured to generate an inhomogeneous magnetic field. The inhomogeneous magnetic field may cause a first coupling of an electric charge state of the electron and a spin state of the electron. The device may comprise a resonator configured to confine a photon. An electric-dipole interaction may cause a second coupling of an electric charge state of the electron to an electric field of the photon.

Abstract: Methods, devices, and systems are described for storing and transferring quantum information. An example device may comprise at least one semiconducting layer, one or more conducting layers configured to define at least two quantum states in the at least one semiconducting layer and confine an electron in or more of the at least two quantum states, and a magnetic field source configured to generate an inhomogeneous magnetic field. The inhomogeneous magnetic field may cause a first coupling of an electric charge state of the electron and a spin state of the electron. The device may comprise a resonator configured to confine a photon. An electric-dipole interaction may cause a second coupling of an electric charge state of the electron to an electric field of the photon.

Abstract: Systems and methods for composite quantum gate calibration for a quantum computing system are provided. In some implementations, a method includes accessing a unitary gate model describing a composite quantum gate. The unitary gate model includes a plurality of gate parameters. The method includes implementing the composite quantum gate for a plurality of gate cycles on the quantum system to amplify the plurality of gate parameters. The method includes obtaining a measurement of a state of the quantum system after implementing the composite quantum gate for the plurality of gate cycles. The method includes determining at least one of the plurality of gate parameters based at least in part on the measurement of the state of the quantum system. The method includes calibrating the composite quantum gate for the quantum computing system based at least in part on the plurality of gate parameters.

Abstract: Methods, devices, and systems are described for storing and transferring quantum information. An example device may comprise at least one semiconducting layer, one or more conducting layers configured to define at least two quantum states in the at least one semiconducting layer and confine an electron in or more of the at least two quantum states, and a magnetic field source configured to generate an inhomogeneous magnetic field. The inhomogeneous magnetic field may cause a first coupling of an electric charge state of the electron and a spin state of the electron. The device may comprise a resonator configured to confine a photon. An electric-dipole interaction may cause a second coupling of an electric charge state of the electron to an electric field of the photon.

Abstract: Methods, devices, and systems are described for performing quantum operations. An example device at least one magnetic field source configured to supply an inhomogeneous magnetic field, at least one semiconducting layer, and one or more conducting layers configured to: define at least two quantum states in the at least one semiconducting layer, and cause, based on an oscillating electrical signal supplied by the one or more conducting layers, an electron to move back and forth between the at least two quantum states in the presence of the inhomogeneous magnetic field. The movement of the electron between the at least two quantum states may generate an oscillating magnetic field to drive a quantum transition between a spin-up state and spin-down state of the electron thereby implementing a qubit gate on a spin state of the electron.

Abstract: Methods, devices, and systems are described for storing and transferring quantum information. An example device may comprise at least one semiconducting layer, one or more conducting layers configured to define at least two quantum states in the at least one semiconducting layer and confine an electron in or more of the at least two quantum states, and a magnetic field source configured to generate an inhomogeneous magnetic field. The inhomogeneous magnetic field may cause a first coupling of an electric charge state of the electron and a spin state of the electron. The device may comprise a resonator configured to confine a photon. An electric-dipole interaction may cause a second coupling of an electric charge state of the electron to an electric field of the photon.