All-optical preparation of coherent dark states of a single rare earth ion spin in a crystal

TL;DR

This paper demonstrates all-optical creation of a coherent dark state in a single cerium ion within a crystal, advancing quantum control techniques for solid-state qubits.

Contribution

It is the first to achieve all-optical coherent dark state preparation of a single rare earth ion in a solid, specifically cerium in YAG, under coherent population trapping conditions.

Findings

Successful generation of a coherent dark state in a single cerium ion.

Narrow, spectrally stable optical transitions observed.

Feasibility of interfacing single photons with a single electron spin confirmed.

Abstract

All-optical addressing and control of single solid-state based qubits allows for scalable architectures of quantum devices such as quantum networks and quantum simulators. So far, all-optical addressing of qubits was demonstrated only for color centers in diamond and quantum dots. Here, we demonstrate generation of coherent dark state of a single rare earth ion in a solid, namely a cerium ion in yttrium aluminum garnet (YAG). The dark state was formed under the condition of coherent population trapping. Furthermore, high-resolution spectroscopic studies of native and implanted single Ce ions have been performed. They revealed narrow and spectrally stable optical transitions between the spin sublevels of the ground and excited optical states, indicating the feasibility of interfacing single photons with a single electron spin of a cerium ion.