Optical coupling between a single tin-vacancy center and a photonic crystal cavity in diamond
Optical coupling between a single tin-vacancy center and a photonic crystal cavity in diamond lead image
Color centers in diamond are defects in the crystal lattice, where carbon atoms are replaced by different kinds of atoms, and adjacent lattice sites are empty. Due to their bright single photon emission and optically accessible spins, color centers can be promising solid state quantum emitters for future quantum information processing and quantum networks.
In combination with their good spin properties, tin-based vacancy centers are well suited for integration into nanophotonic platforms because of their strong and stable zero-phonon line emission in nanostructures. Kuruma et al. demonstrated optical coupling of a single tin-vacancy center to a free-standing photonic crystal nanocavity in diamond.
The authors fabricated high-quality factor photonic crystal nanobeam cavities in single crystal diamond substrate using a quasi-isotropic etching technique and incorporated the tin-vacancy centers into the nanocavities to enhance the center’s zero-phonon line emission and its collection efficiency.
They observed a large Purcell enhancement of a single tin-vacancy center emission rate by a factor of 16, compared to bulk, and realized near unity of 95% coupling efficiency of the center to the cavity, which means that most emitted photons from the center were channeled into the cavity mode.
Going forward, the collection efficiency of enhanced single photon emission from the center can be further improved by incorporating tapered waveguide structures for optical fiber coupling into current photonic architectures.
“This will be important to realize efficient spin-photon interfaces using tin-vacancy centers.” said author Kazuhiro Kuruma.
“We are expecting that our developed platform will be a great help not only for efficient generation of cluster states, but also ultrafast coherent optical control of spins,” said author Benjamin Pingault.
Source: “Coupling of a single tin-vacancy center to a photonic crystal cavity in diamond,” by Kazuhiro Kuruma, Benjamin Pingault, Cleaven Chia, Dylan Renaud, Patrick Hoffmann, Satoshi Iwamoto, Carsten Ronning, and Marko Lončar, Applied Physics Letters (2021). The article can be accessed at https://doi.org/10.1063/5.0051675 .
