Impulsive Spin-Motion Entanglement for Fast Quantum Computation and Sensing

TL;DR

This paper demonstrates rapid entanglement of spin and motional states in a trapped ion using ultrafast laser pulses, achieving high-fidelity quantum operations faster than traditional timescales, advancing quantum computing and sensing.

Contribution

It introduces a method for entangling spin and motion in a trapped ion with ultrafast laser pulses, surpassing previous speed limitations for quantum operations.

Findings

Achieved entanglement with a 16 ps laser pulse.

Operation speed exceeds motional and spin precession timescales.

Fidelity of single qubit operations is approximately 97%.

Abstract

We perform entanglement of spin and motional degrees of freedom of a single, ground-state trapped ion through the application of a $16$ ps laser pulse. The duration of the interaction is significantly shorter than both the motional timescale ($30$ $\mu$s) and spin precession timescale ($1$ ns) , demonstrating that neither sets a fundamental speed limit on this operation for quantum information processing. Entanglement is demonstrated through the collapse and revival of spin coherence as the spin components of the wavefunction separate and recombine in phase space. We infer the fidelity of these single qubit operations to be $(97^{+3}_{-4})\%$.