Diamond-based single-photon emitters

TLDR

Efficient fabrication of quantum building blocks, such as single‑photon sources, is essential for quantum technologies, and color‑center diamond emitters provide a photostable, room‑temperature solid‑state platform for quantum communication, computation, nanoscopy, and bio‑marking. This review surveys the state of the art of diamond‑based single‑photon emitters and highlights their fabrication methodologies. The authors review experimental techniques for characterizing diamond emitters’ photophysical properties and discuss their use in quantum key distribution, bio‑marking, and sub‑diffraction imaging. The review concludes by outlining the main challenges and future perspectives for deploying diamond emitters in quantum information processing.

Abstract

The exploitation of emerging quantum technologies requires efficient fabrication of key building blocks. Sources of single photons are extremely important across many applications as they can serve as vectors for quantum information—thereby allowing long-range (perhaps even global-scale) quantum states to be made and manipulated for tasks such as quantum communication or distributed quantum computation. At the single-emitter level, quantum sources also afford new possibilities in terms of nanoscopy and bio-marking. Color centers in diamond are prominent candidates to generate and manipulate quantum states of light, as they are a photostable solid-state source of single photons at room temperature. In this review, we discuss the state of the art of diamond-based single-photon emitters and highlight their fabrication methodologies. We present the experimental techniques used to characterize the quantum emitters and discuss their photophysical properties. We outline a number of applications including quantum key distribution, bio-marking and sub-diffraction imaging, where diamond-based single emitters are playing a crucial role. We conclude with a discussion of the main challenges and perspectives for employing diamond emitters in quantum information processing.