Abstract
The realization of quantum networks critically depends on establishing efficient, coherent light-matter interfaces. Optically active spins in diamond have emerged as promising quantum nodes based on their spin-selective optical transitions, long-lived spin ground states, and potential for integration with nanophotonics. Tin-vacancy () centers in diamond are of particular interest because they exhibit narrow-linewidth emission in nanostructures and possess long spin coherence times at temperatures above 1 K. However, a nanophotonic interface for centers has not yet been realized. Here, we report cavity enhancement of the emission of centers in diamond. We integrate centers into one-dimensional photonic crystal resonators and observe a 40-fold increase in emission intensity. The Purcell factor of the coupled system is 25, resulting in a channeling of the majority of photons (90%) into the cavity mode. Our results pave the way for the creation of efficient, scalable spin-photon interfaces based on centers in diamond.
- Received 11 March 2021
- Accepted 26 May 2021
DOI:https://doi.org/10.1103/PhysRevX.11.031021
Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.
Published by the American Physical Society
Physics Subject Headings (PhySH)
Viewpoint
ViewpointTin Qubits Give Diamond a New Shine
Published 26 July 2021
Nanophotonic devices based on tin-vacancy qubits in diamond show promise as building blocks of quantum repeaters, an important step toward the realization of long-range quantum networks.
See more in Physics
Popular Summary
Diamond color centers—atomic defects in the crystal lattice—are leading candidates for optically accessible quantum memories, which provide the basis quantum networks. In particular, tin-vacancy centers (in which a pair of neighboring carbon atoms in a diamond is replaced by a tin atom and a vacancy) have emerged as strong qubit candidates. Tin-vacancy centers possess excellent optical properties in nanostructured material while featuring a highly coherent spin at temperatures above 1 K. However, fully harnessing their optical properties requires integration into an optical cavity. Here, we present a critical step for developing a quantum network based on color centers at cryogenic temperatures by coupling tin-vacancy centers to nanophotonic resonators.
In our experiments, we integrate tin-vacancy centers into 1D photonic crystal resonators and observe a 40-fold increase in emission intensity. We achieve this milestone by combining a recently developed method to generate high-quality emitters and a unique fabrication technique to create suspended structures in bulk diamond.
The observed significant increase in the emission of the tin-vacancy center coupled to the cavity may enable future experiments with spin-photon entanglement, paving the way toward the development of scalable quantum networks.
