Northrop Grumman Systems Corporation

Other

James Edward Baumgardner

Aaron A Pesetski

Quentin P Herr

John Xavier Przybysz

Anna Y Herr

Donald Lynn Miller

John D Adam

Gordon R Neufeld

Rupert M Lewis

Hong Zhang

Norman Goldstein

Ouentin P Herr

Jim Murduck

A phase quantum bit is disclosed. In one embodiment, the phase quantum bit may comprise a Josephson junction and a distributed element coupled to the Josephson junction. The distributed element provides a capacitive component and an inductive component of the phase quantum bit.

Phase quantum bit

Systems and methods are provided for improving fidelity of a quantum operation on a quantum bit of interest. A controlled quantum gate operation, controlled by the quantum bit of interest, id performed on an ancillary quantum bit. An energy state of the ancillary quantum bit is measured to facilitate the improvement of the fidelity of the quantum operation.

Methods of increasing fidelity of quantum operations

One embodiment of the invention includes a quantum processor system. The quantum processor system includes a first resonator having a first characteristic frequency and a second resonator having a second characteristic frequency greater than the first characteristic frequency. A qubit cell is coupled to each of the first resonator and the second resonator. The qubit cell has a frequency tunable over a range of frequencies including the first characteristic frequency and the second characteristic frequency. A classical control mechanism is configured to tune the frequency of the qubit cell as to transfer quantum information between the first resonator and the second resonator.

Quantum processor

Systems and methods are provided for performing a quantum error correction. An error correction is performed on each of a plurality of qubit sets restore a desired basis state of the qubit set. Each qubit set corresponds to an associated logical qubit. A number of corrected qubits at each of the plurality of qubit sets are recorded. A first set of the plurality of logical qubits having a first state and a second set of the plurality of logical qubits having a second state are determined. One of the first set of logical qubits and the second set of logical qubits are corrected according to the recorded numbers of corrected qubits.

Error correction in quantum computing system

One embodiment of the invention includes a quantum system. The system includes a superconducting qubit that is controlled by a control parameter to manipulate a photon for performing quantum operations. The system also includes a quantum resonator system coupled to the superconducting qubit and which includes a first resonator and a second resonator having approximately equal resonator frequencies. The quantum resonator system can represent a first quantum logic state based on a first physical quantum state of the first and second resonators with respect to storage of the photon and a second quantum logic state based on a second physical quantum state of the first and second resonators with respect to storage of the photon.

System and method for phase error reduction in quantum systems

In one embodiment, the disclosure relates to a method and apparatus for controlling the energy state of a qubit by bringing the qubit into and out of resonance by coupling the qubit to a flux quantum logic gate. The qubit can be in resonance with a pump signal, with another qubit or with some quantum logic gate. In another embodiment, the disclosure relates to a method for controlling a qubit with RSFQ logic or through the interface between RSFQ and the qubit.

Method and apparatus for controlling qubits with single flux quantum logic

Systems and methods are provided for performing a quantum gate operation. A first classical control parameter, configured to tune an associated frequency of a first qubit, is adjusted from a first value to a second value. The first value is selected such that the first qubit is tuned far from a characteristic frequency of an associated resonator, and the second value is selected such that the first qubit is tuned near to the characteristic frequency of the resonator. A second classical control parameter, configured to tune an associated frequency of a second qubit, is adjusted from a third value to a fourth value. The third value is selected such that the second qubit is tuned far from the characteristic frequency of the resonator. The first classical control parameter is returned to the first value. The second classical control parameter is returned to the third value.

Quantum logic gates utilizing resonator mediated coupling

Systems and methods are provided for performing a quantum gate operation. A first classical control parameter is associated with a first qubit and coupled to a resonator. The first classical control parameter is transitioned from a first control value to a second control value. The first classical control parameter is returned from the second control value to the first control value via an adiabatic sweep operation, as to permit a transfer of energy between the first qubit and the resonator that causes a change in the quantum state of the qubit and resonator.

Quantum gate operations with a common coupled resonator

In one embodiment, the disclosure relates to a single flux quantum (SFQ) signal transmission line powered by an AC power source. The AC power source supplies power to a transformer having a primary winding and a secondary winding. The primary winding receives the AC signal and the secondary winding communicates the signal to the SFQ transmission line. The transmission line can optionally include an input filter circuit for receiving the incoming SFQ pulse. The filter circuit can have a resistor and an inductor connected in parallel. In an alternative arrangement, the filter circuit can comprise of an inductor. A first Josephson junction can be connected to the filter circuit and to the secondary winding. The Josephson junction triggers in response to the incoming SFQ pulse and regenerates a pulse signal in response to a power discharge from the secondary winding.

Growing community of inventors

Odenton, MD, United States of America

James Edward Baumgardner