Towards the speed limit of high fidelity 2-qubit gates

Abstract

Most implementations of quantum gate operations rely on external control fields to drive the evolution of the quantum system. Generating these control fields requires significant efforts to design the suitable control Hamiltonians. Furthermore, any error in the control fields reduces the fidelity of the implemented control operation with respect to the ideal target operation. Achieving sufficiently fast gate operations at low error rates remains therefore a huge challenge. In this work, we present a novel approach to overcome this challenge by eliminating, for specific gate operations, the time-dependent control fields entirely. This approach appears useful for maximising the speed of the gate operation while simultaneously eliminating relevant sources of errors. We present an experimental demonstration of the concept in a single nitrogen-vacancy (NV) center in diamond at room temperature.

Accepted in Physical Review Letters

References in corpus (6)

• High-sensitivity diamond magnetometer with nanoscale resolution
• Scanning magnetic field microscope with a diamond single-spin sensor
• Decoherence-protected quantum gates for a hybrid solid-state spin register
• Complete universal quantum gate set approaching fault-tolerant thresholds with superconducting qubits
• Detection and control of individual nuclear spins using a weakly coupled electron spin
• Coherence of single spins coupled to a nuclear spin bath of varying density

Cited by in corpus (6)

• Fast Quantum State Tomography in the Nitrogen Vacancy Center of Diamond
• Quantum Gate Generation in Two-Level Open Quantum Systems by Coherent and Incoherent Photons Found with Gradient Search
• Robustness of Variational Quantum Algorithms against stochastic parameter perturbation
• Fidelity-dissipation relations in quantum gates
• Zero-Noise Extrapolation via Cyclic Permutations of Quantum Circuit Layouts
• Role of overparametrization in quantum approximate optimization