Truncated Metallo-Dielectric Omnidirectional Reflector: Collecting Single Photons in the Fundamental Gaussian Mode with 95% Efficiency

Wancong Li,Luis Morales-Inostroza,Jan Renger,Weiwang Xu,Xue-Wen Chen,Pu Zhang,Stephan Götzinger

doi:10.1021/acsphotonics.0c00730

Abstract

We propose a novel antenna structure which funnels single photons from a single emitter with unprecedented efficiency into a low-divergence fundamental Gaussian mode. Our device relies on the concept of creating an omnidirectional photonic bandgap to inhibit unwanted large-angle emission and to enhance small-angle defect-guided-mode emission. The new photon collection strategy is intuitively illustrated, rigorously verified and optimized by implementing an efficient body-of-revolution finite-difference time-domain method for in-plane dipole emitters. We investigate a few antenna designs to cover various boundary conditions posed by fabrication processes or material restrictions and theoretically demonstrate that collection efficiencies into the fundamental Gaussian mode exceeding 95% are achievable. Our antennas are broadband, insensitive to fabrication imperfections and compatible with a variety of solid-state emitters such as organic molecules, quantum dots and defect centers in diamond. Unidirectional and low-divergence Gaussian-mode emission from a single emitter may enable the realization of a variety of photonic quantum computer architectures as well as highly efficient light-matter interfaces.

Highlights

We propose a novel antenna structure that funnels single photons from a single emitter with unprecedented efficiency into a low-divergence fundamental Gaussian mode
The big advantage of a solid state approach is the ability to precisely control the environment of an emitter through micro- and nanostructuring and to engineer the emission properties of an emitter.[7−10] Solid-state single quantum emitters have become highly efficient and versatile sources of single photons, reaching a certain level of maturity.[6,11−13] efficient photon collection alone is for many applications not sufficient
The top medium may have the form of a half sphere, which functions as a so-called solid immersion lens (SIL)

Summary

■ RESULTS AND DISCUSSION

Our calculations show that deviations as large as 25 nm cause changes of 0.01% and 0.4% to the collection efficiency and projection efficiency, respectively This demonstrates that the device performance is quite robust against deviations of the emitter from the optimal position and relaxes the requirements on fabrication precision. For self-assembled InGaAs quantum dots, nanofabrication of the host material may degrade the spectral properties of the quantum dots,[52] which can be remedied by applying surface passivation approaches[52] and by controlling the charge noise via electric gating.[23,53] The antenna design can be adjusted to take practical requirements into account, such as the use of conductive transparent materials or atomic-layer deposition of additional materials around the emitter

■ CONCLUSIONS

■ REFERENCES

■ ACKNOWLEDGMENTS