Coherent spin dynamics in gadolinium-doped CaWO4 crystal

TL;DR

This paper reports the first observation of Rabi oscillations in gadolinium-doped CaWO$_4$ crystals, demonstrating potential for quantum information processing with an 8-level Gd$^{3+}$ ion system.

Contribution

It presents the first experimental observation of Rabi oscillations in Gd$^{3+}$ ions in CaWO$_4$, with a theoretical model explaining the spin dynamics and coherence.

Findings

Rabi oscillations observed in Gd$^{3+}$ ensemble

Spin coherence times characterized under various microwave fields

The 8-level Gd$^{3+}$ ground state can serve as a three-qubit system

Abstract

We report the first observation of Rabi oscillations in the spin-7/2 ensemble of trivalent gadolinium ions hosted in CaWO$_4$ single crystal. A number of transitions within the lowest electronic multiplet $^8S_{7/2}$ of Gd$^{3+}$ ion are studied using a combination of continuous-wave and pulsed electron paramagnetic resonance spectroscopy. The corresponding Rabi damping curves and the spin coherence times are detected at varying strengths of the microwave field. These data are well reproduced by a theoretical model which accounts for the intrinsic inhomogeneity of the microwave field within the microwave resonator and the magnetic dipole interactions in the diluted spin ensemble. The results indicate that the studied 8-level ground manifold of Gd$^{3+}$ ion can represent an effective three qubit quantum system.