Deterministic amplification of Schrödinger cat states in circuit quantum electrodynamics

Joo, Jaewoo; Elliott, Matthew; Oi, Daniel K. L.; Ginossar, Eran; Spiller, Timothy P.

doi:10.1088/1367-2630/18/2/023028

Cited by 10 publications

(9 citation statements)

References 71 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For example, the outcomes of the teleported state before the classical feedback contain one of the single-qubit gates ( , , ) probabilistically while a deterministic gate for needs to transform the CV state from N α ( a | α 〉 + b |− α 〉) to N α ( a | α 〉 − b |− α 〉). This gate could be viable by performing a photon-shifting gate proposed in 85 based on the setup in Fig. 2(a) .…”

Section: Discussionmentioning

confidence: 99%

“…For creating multi-partite ECSs, cross-Kerr interaction could be used in the multiple-cavity architecture joined by mediating qubits in order to keep the capability of CV-qubit operations in a dispersive regime. Furthermore, a full simulation of creating an ECS and of performing the hybrid quantum information processing in the 2C3Q architecture will be presented in later work [47].…”

Section: B Conclusionmentioning

confidence: 99%

See 1 more Smart Citation

Efficient scheme for hybrid teleportation via entangled coherent states in circuit quantum electrodynamics

Joo

Ginossar

2016

Sci Rep

Self Cite

View full text Add to dashboard Cite

We propose a deterministic scheme for teleporting an unknown qubit state through continuous-variable entangled states in superconducting circuits. The qubit is a superconducting two-level system and the bipartite quantum channel is a microwave photonic entangled coherent state between two cavities. A Bell-type measurement performed on the hybrid state of solid and photonic states transfers a discrete-variable unknown electronic state to a continuous-variable photonic cat state in a cavity mode. In order to facilitate the implementation of such complex protocols we propose a design for reducing the self-Kerr nonlinearity in the cavity. The teleporation scheme enables quantum information processing operations with circuit-QED based on entangled coherent states. These include state verification and single-qubit operations with entangled coherent states. These are shown to be experimentally feasible with the state of the art superconducting circuits.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: B Conclusionmentioning

confidence: 99%

Efficient scheme for hybrid teleportation via entangled coherent states in circuit quantum electrodynamics

Joo

Ginossar

2016

Sci Rep

Self Cite

View full text Add to dashboard Cite

show abstract

“…A periodic boundary condition is applied here in normalised |ψ(x) implies |ψ(0) = |ψ(1) for 0 ≤ x ≤ 1 because we utilise an unitary operator to describe the quantum subtractor in the domain. In fact, the ideal translation operator could be implemented beyond the finite regions in a specific physical system as a non-unitary gate (e.g., a photon shift operation [13]).…”

Section: B Expectation Value Of Quantum Subtractor â † For Derivative...mentioning

confidence: 99%

Quantum variational PDE solver with machine learning

Joo,

Moon

2021

Preprint

Self Cite

View full text Add to dashboard Cite

To solve nonlinear partial differential equations (PDEs) is one of the most common but important tasks in not only basic sciences but also many practical industries. We here propose a quantum variational (QuVa) PDE solver with the aid of machine learning (ML) schemes to synergise two emerging technologies in mathematically hard problems. The core quantum processing in this solver is to calculate efficiently the expectation value of specially designed quantum operators. For a large quantum system, we only obtain data from measurements of few control qubits to avoid the exponential cost in the measurements of the whole quantum system and optimise a pathway to find possible solution sets of the desired PDEs using ML techniques. As an example, a few different types of the second-order DEs are examined with randomly chosen samples and a regression method is implemented to chase the best candidates of solution functions with another trial samples. We demonstrated that a three-qubit system successfully follows the pattern of analytical solutions of three different DEs with high fidelity since the variational solutions are given by a necessary condition to obtain the exact solution of the DEs. Thus, we believe that final solution candidate sets are efficiently extracted from the QuVa PDE solver with the support of ML techniques and this algorithm could be beneficial to search for the solutions of complex mathematical problems as well as to find good ansatzs for eigenstates in large quantum systems (e.g., for quantum chemistry).

show abstract

“…It is known that the SCSs with a sufficiently large amplitude are utilized for fault-tolerant continuous-variable QI processing [24]. Because this method brings very high fidelity to SCSs at small amplitudes, the amplification of the SCSs may be required for practical QI processing [25,26]. In addition, the traveling SCSs are also useful resource states for performing nonlocality tests [27][28][29][30][31][32][33] and for testing indistinguishability of macroscopic states [34].…”

Section: Introductionmentioning

confidence: 99%

Implementation of Traveling Odd Schrödinger Cat States in Circuit-QED

2016

Self Cite

View full text Add to dashboard Cite

Abstract:We propose a realistic scheme of generating a traveling odd Schrödinger cat state and a generalized entangled coherent state in circuit quantum electrodynamics (circuit-QED). A squeezed vacuum state is used as the initial resource of nonclassical states, which can be created through a Josephson traveling-wave parametric amplifier, and travels through a transmission line. Because a single-photon subtraction from the squeezed vacuum gives an odd Schrödinger cat state with very high fidelity, we consider a specific circuit-QED setup consisting of the Josephson amplifier creating the traveling resource in a line, a beam-splitter coupling two transmission lines, and a single photon detector located at the end of the other line. When a single microwave photon is detected by measuring the excited state of a superconducting qubit in the detector, a heralded cat state is generated with high fidelity in the opposite line. For example, we show that the high fidelity of the outcome with the ideal cat state can be achieved with appropriate squeezing parameters theoretically. As its extended setup, we suggest that generalized entangled coherent states can be also built probabilistically and that they are useful for microwave quantum information processing for error-correctable qudits in circuit-QED.

show abstract

Deterministic amplification of Schrödinger cat states in circuit quantum electrodynamics

Cited by 10 publications

References 71 publications

Efficient scheme for hybrid teleportation via entangled coherent states in circuit quantum electrodynamics

Efficient scheme for hybrid teleportation via entangled coherent states in circuit quantum electrodynamics

Quantum variational PDE solver with machine learning

Implementation of Traveling Odd Schrödinger Cat States in Circuit-QED

Contact Info

Product

Resources

About