Certification of continuous-variable gates using average channel-fidelity witnesses
arXiv:1812.01968 · doi:10.1088/2058-9565/ac051a
Abstract
We introduce witnesses for the average channel fidelity between a known target gate and an arbitrary unknown channel, for continuous-variable (CV) systems. These are observables whose expectation value yields a tight lower bound to the average channel fidelity in question, thus constituting a practical tool for certification of experimental CV gates. Our framework applies to a broad class of target gates. Here, we focus on three specific types of targets: multi-mode Gaussian unitary channels, single-mode coherent state amplifiers, and the single-mode (non-Gaussian) cubic phase gate, which is a crucial ingredient for CV universal quantum computation. Our witnesses are experimentally-friendly as they rely exclusively on Gaussian measurements, even for the non-Gaussian-target case. Moreover, in all three cases, they can be measured efficiently in the estimation error and failure probability , as well as in the number of modes for the Gaussian-target case. To end up with, our approach for the Gaussian-target case relies on an improved measurement scheme for Gaussian state-fidelity witnesses, which is polynomially and exponentially more efficient in and , respectively, than previous schemes. The latter constitutes an interesting byproduct result on its own. Our findings are relevant to the experimental validation of many-body quantum technologies.
arXiv comment15 pages
References in corpus (50)
- Gaussian Quantum Information
- Encoding a qubit in an oscillator
- Predicting Many Properties of a Quantum System from Very Few Measurements
- Quantum computation over continuous variables
- Continuous-variable optical quantum state tomography
- Quantum state tomography via compressed sensing
- Randomized Benchmarking of Quantum Gates
- Advances in Quantum Teleportation
- Prescription for experimental determination of the dynamics of a quantum black box
- Robust randomized benchmarking of quantum processes
- A simple formula for the average gate fidelity of a quantum dynamical operation
- Efficient quantum state tomography
- Complete Characterization of a Quantum Process: the Two-Bit Quantum Gate
- Exact and Approximate Unitary 2-Designs: Constructions and Applications
- Squeezing as an irreducible resource
- Scalable Noise Estimation with Random Unitary Operators
- Direct Fidelity Estimation from Few Pauli Measurements
- Quantum Process Tomography: Resource Analysis of Different Strategies
- Fidelity and Concurrence of conjugated states
- The Real Symplectic Groups in Quantum Mechanics and Optics
- Quantum Tomography via Compressed Sensing: Error Bounds, Sample Complexity, and Efficient Estimators
- Quantum Computing with Continuous-Variable Clusters
- Ancilla-assisted quantum process tomography
- Noiseless Linear Amplification and Distillation of Entanglement
- Practical characterization of quantum devices without tomography
- A high-fidelity noiseless amplifier for quantum light states
- Permutationally invariant quantum tomography
- Implementation of a non-deterministic optical noiseless amplifier
- Criteria for Continuous-Variable Quantum Teleportation
- Quantum benchmark for storage and transmission of coherent states
- Noise-Powered Probabilistic Concentration of Phase Information
- Heralded Noiseless Amplification of a Photon Polarization Qubit
- Implementation of a quantum cubic gate by adaptive non-Gaussian measurement
- Permutationally invariant state reconstruction
- Reliable quantum certification for photonic quantum technologies
- Universal Quantum Computing with Measurement-Induced Continuous-Variable Gate Sequence in a Loop-Based Architecture
- Scalable randomized benchmarking of non-Clifford gates
- Repeat-until-success cubic phase gate for universal continuous-variable quantum computation
- Generation and characterization of resource state for nonlinear cubic phase gate
- Recovering quantum gates from few average gate fidelities
- Fidelity witnesses for fermionic quantum simulations
- Optimal design and quantum benchmarks for coherent state amplifiers
- Optimal strategies for estimating the average fidelity of quantum gates
- Fidelity criterion for quantum-domain transmission and storage of coherent states beyond unit-gain constraint
- Progress toward scalable tomography of quantum maps using twirling-based methods and information hierarchies
- Selective and Efficient Quantum State Tomography and its Application to Quantum Process Tomography
- Characterizing the performance of continuous-variable Gaussian quantum gates
- Client-friendly continuous-variable blind and verifiable quantum computing
- Test one to test many: a unified approach to quantum benchmarks
- Schmidt-number benchmarks for continuous-variable quantum devices