Fast dynamical decoupling of the Molmer-Sorensen entangling gate

Abstract

Engineering entanglement between quantum systems often involves coupling through a bosonic mediator, which should be disentangled from the systems at the operation's end. The quality of such an operation is generally limited by environmental and control noise. One of the prime techniques for suppressing noise is by dynamical decoupling, where one actively applies pulses at a rate that is faster than the typical time scale of the noise. However, for boson-mediated gates, current dynamical decoupling schemes require executing the pulses only when the boson and the quantum systems are disentangled. This restriction implies an increase of the gate time by a factor of $\sqrt{N}$, with $N$ being the number of pulses applied. Here we propose and realize a method that enables dynamical decoupling in a boson mediated system where the pulses can be applied while spin-boson entanglement persists, resulting in an increase in time that is at most a factor of $\frac{\pi }{2}$, independently of the number of pulses applied. We experimentally demonstrate the robustness of our fast dynamically decoupled entangling gate to ${\sigma }_z$ noise with ions in a Paul trap.

References in corpus (10)

• Coupling Superconducting Qubits via a Cavity Bus
• Towards fault-tolerant quantum computing with trapped ions
• Phonon-induced spin-spin interactions in diamond nanostructures: application to spin squeezing
• Fast and robust two-qubit gates for scalable ion trap quantum computing
• High-fidelity trapped-ion quantum logic using near-field microwaves
• Comparison of dynamical decoupling protocols for a nitrogen-vacancy center in diamond
• Deterministic entanglement of ions in thermal states of motion
• Phase-modulated decoupling and error suppression in qubit-oscillator systems
• Multi-Qubit Gate with Trapped Ions for Microwave and Laser-Based Implementation
• Universal Set of Gates for Microwave Dressed-State Quantum Computing

Cited by in corpus (3)

• Robust and resource-efficient microwave near-field entangling ${}^9$Be${}^{+}$ gate
• Single-step implementation of high fidelity $n$-bit Toffoli gate
• Randomisation of Pulse Phases for Unambiguous and Robust Quantum Sensing