Fabrication of Nanophotonic Structures in Silicon Carbide with Integrated Defects and an Efficient Taper-Fiber Interface*

Defect centers in silicon carbide (SiC) have high potential for quantum information applications. Silicon vacancies (V_Si) in SiC show highly coherent spin-optical properties [1] up to temperatures of 20K [2], even after nanophotonic integration [3], [4]. It was also shown that triangular nanophotonics can efficiently guide the emission of these defects, while providing cavity designs that are resilient to fabrication errors [5].

 

To boost the overall emission of V_Si centers and increase the Debye-Waller factor (resonant emission), photonic crystal cavities (PCC) are highly desirable. Towards this goal, we show direct waveguide-to-fibre coupling [6], achieving near-deterministic efficiencies. We also model the observation of reduced efficiencies, which gives guidelines for improved tapered fiber generation. With this technology, we show an efficient room-temperature single-photon source based on a fiber-coupled V_Si center. Our latest steps towards low-temperature integration, as well as fabrication of PCCs will be discussed, too.

 

[1] R. Nagy et al., Nat. Commun. 10, 1954 (2019).

[2] P. Udvarhelyi et al., Phys. Rev. Appl. 13, 054017 (2020).

[3] C. Babin et al., Nat. Mater. 21, 67 (2022).

[4] D.M. Lukin et al., arXiv.2202.04845 (2022).

[5] S. Majety et al., J. Phys. Photonics 3, 034008 (2021).

[6] M. J. Burek et al., Phys. Rev. Appl. 8, 024026 (2017).