Probing the collective dynamics of nuclear spin bath in a rare-earth ion doped crystal

TL;DR

This paper investigates the collective nuclear spin dynamics in rare-earth ion doped crystals using dynamical decoupling spectroscopy, revealing insights into spin bath configuration, flip-flop times, and potential quantum sensing applications.

Contribution

It introduces a method to probe nuclear spin bath dynamics in rare-earth crystals and demonstrates their use as magnetic quantum sensors.

Findings

Measured nuclear spin flip-flop times of around 1 second.

Analyzed the configuration of the nuclear spin bath.

Demonstrated rare-earth ions as magnetic field sensors.

Abstract

Probing collective spin dynamics is a current challenge in the field of magnetic resonance spectroscopy and has important applications in material analysis and quantum information protocols. Recently, the rare-earth ion doped crystals are an attractive candidate for making long-lived quantum memory. Further enhancement of its performance would benefit from the direct knowledge on the dynamics of nuclear-spin bath in the crystal. Here we detect the collective dynamics of nuclear-spin bath located around the rare-earth ions in a crystal using dynamical decoupling spectroscopy method. From the measured spectrum, we analyze the configuration of the spin bath and characterize the flip-flop time between two correlated nuclear spins in a long time scale ($\sim $1s). Furthermore, we experimentally demonstrate that the rare-earth ions can serve as a magnetic quantum sensor for external magnetic field. These results suggest that the rare-earth ion is a useful probe for complex spin dynamics in solids and enable quantum sensing in the low-frequency regime, revealing promising possibilities for applications in diverse fields.