Simultaneous coherence enhancement of optical and microwave transitions in solid-state electronic spins

TL;DR

This paper demonstrates simultaneous enhancement of optical and microwave coherence times in a solid-state electronic spin system using isotopic engineering and hyperfine interaction, advancing quantum information applications.

Contribution

The study introduces a method to induce clock transitions in both optical and microwave domains in $^{171}$Yb$^{3+}$:Y$_2$SiO$_5$, achieving long coherence times and potential for quantum technologies.

Findings

Coherence times of over 100 μs in optical and 1 ms in microwave domains.

Simultaneous clock transitions induced by anisotropic hyperfine interaction.

Potential applications in quantum memories and microwave-optical transducers.

Abstract

Solid-state electronic spins are extensively studied in quantum information science, as their large magnetic moments offer fast operations for computing and communication, and high sensitivity for sensing. However, electronic spins are more sensitive to magnetic noise, but engineering of their spectroscopic properties, e.g. using clock transitions and isotopic engineering, can yield remarkable spin coherence times, as for electronic spins in GaAs, donors in silicon and vacancy centres in diamond. Here we demonstrate simultaneously induced clock transitions for both microwave and optical domains in an isotopically purified $^{171}$Yb$^{3+}$:Y$_2$SiO$_5$ crystal, reaching coherence times of above 100 $\mu$s and 1 ms in the optical and microwave domain, respectively. This effect is due to the highly anisotropic hyperfine interaction, which makes each electronic-nuclear state an entangled Bell state. Our results underline the potential of $^{171}$Yb$^{3+}$:Y$_2$SiO$_5$ for quantum processing applications relying on both optical and spin manipulation, such as optical quantum memories, microwave-tooptical quantum transducers, and single spin detection, while they should also be observable in a range of different materials with anisotropic hyperfine interaction.