# Adaptive characterization of spatially inhomogeneous fields and errors in qubit registers

@article{Gupta2020AdaptiveCO, title={Adaptive characterization of spatially inhomogeneous fields and errors in qubit registers}, author={Riddhi Swaroop Gupta and Claire L. Edmunds and Alistair R. Milne and Cornelius Hempel and Michael J. Biercuk}, journal={npj Quantum Information}, year={2020}, volume={6}, pages={1-10} }

New quantum computing architectures consider integrating qubits as sensors to provide actionable information useful for calibration or decoherence mitigation on neighboring data qubits, but little work has addressed how such schemes may be efficiently implemented in order to maximize information utilization. Techniques from classical estimation and dynamic control, suitably adapted to the strictures of quantum measurement, provide an opportunity to extract augmented hardware performance through…

## 5 Citations

Efficient Noise Mitigation Technique for Quantum Computing

- Computer Science, PhysicsArXiv
- 2021

A novel protocol is proposed that efficiently estimates the average output of a noisy quantum device to be used for quantum noise mitigation and demonstrates improved accuracy with efficient noise characterization.

Practical Guide for Building Superconducting Quantum Devices

- PhysicsPRX Quantum
- 2021

Quantum computing offers a powerful new paradigm of information processing that has the potential to transform a wide range of industries. In the pursuit of the tantalizing promises of a universal…

Quantum firmware and the quantum computing stack

- Computer Science
- 2021

Integrated quantum-control protocols could bridge the gap between abstract algorithms and the physical manipulation of imperfect hardware.

Adaptive filtering of projective quantum measurements using discrete stochastic methods

- Physics, Computer SciencePhysical Review A
- 2021

These results are important early demonstrations indicating that a range of concepts and techniques from classical nonlinear filtering theory may be applied to the characterization of quantum systems involving discretized projective measurements, paving the way for broader adoption of control theoretic techniques in quantum technology.

Integration of spectator qubits into quantum computer architectures for hardware tune-up and calibration

- Computer Science, Physics
- 2020

This work focuses on the specific challenge of measuring (``mapping'') spatially inhomogeneous quasi-static calibration errors using spectator qubits dedicated to the task of sensing and calibration, and introduces a novel architectural concept: arranging them spatially according to prescriptions from optimal 2D approximation theory.

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