High Speed, High Fidelity Detection of an Atomic Hyperfine Qubit

TL;DR

This paper introduces a rapid and highly accurate method for detecting the state of a hyperfine qubit in trapped ions, achieving sub-100 microsecond detection times with over 99.9% fidelity, crucial for quantum computing applications.

Contribution

The work presents a simple, efficient detection protocol for $^{171}$Yb$^+$ hyperfine qubits with high collection efficiency and low background noise, significantly improving detection speed and fidelity.

Findings

Detection times of 10.5, 28.1, and 99.8 microseconds achieved.

Detection fidelities of 99%, 99.85%, and 99.915% demonstrated.

Protocol enables fast, high-fidelity qubit state detection for quantum information processing.

Abstract

Fast and efficient detection of the qubit state in trapped ion quantum information processing is critical for implementing quantum error correction and performing fundamental tests such as a loophole-free Bell test. In this work we present a simple qubit state detection protocol for a $^{171}$Yb$^+$ hyperfine atomic qubit trapped in a microfabricated surface trap, enabled by high collection efficiency of the scattered photons and low background photon count rate. We demonstrate average detection times of 10.5, 28.1 and 99.8\,$\upmu$s, corresponding to state detection fidelities of 99%, 99.85(1)% and 99.915(7)%, respectively.