Diamond photonics

Gibson, Brant, Huntington, Shane

Since diamond can act as both an optical source and a waveguiding material, there is a great deal of interest in realizing true quantum information processing (QIP) using an all-diamond solution. A key motivator for the need of diamond photonic devices is the requirement to connect single photon centers (SPS) together. Optical structures such as waveguides or microcavities can enable the transfer of these pieces of quantum information. The fabrication of monolithic photonic devices in diamond for QIP has attracted significant attention from a number of research groups. This chapter examines the cunent state-of-the-art with regards to micro-machining diamond, presents a number of photonic structures and waveguiding results, and examines the future direction of diamond photonics.

Igor Aharonovich, Andrew D. Greentree, Steven Prawer

Assegid M. Flatae, Florian Sledz, Haritha Kambalathmana +8 more

Single-color centers in thin polycrystalline diamond membranes allow the platform to be used in integrated quantum photonics, hybrid quantum systems, and other complex functional materials. While single-crystal diamond membranes are still technologically challenging to fabricate as they cannot be grown on a non-diamond substrate, free-standing polycrystalline diamond membranes can be conveniently fabricated at large-scale from nanocrystalline diamond seeds on a substrate that can be selectively etched. However, their practical application for quantum photonics is so far limited by crystallographic defects, impurities, graphitic grain boundaries, small grain sizes, scattering loss, and strain. In this paper, we report on a single-photon source based on silicon-vacancy color centers in a polycrystalline diamond membrane. We discuss the spectroscopic approach and quantify the photon statistics, obtaining a g2(0) ≈ 0.04. Our findings hold promise for introducing polycrystalline diamond to quantum photonics and hybrid quantum systems.

Sophie W. Ding, Chang Jin, Zixi Li +9 more

Diamond photonics has enabled efficient interfaces for quantum memories and is predicted to be a critical component of quantum networks. However, scalable network architectures require spatial, temporal, and spectral control of photons, which relies on nonlinear and electro-optic functionalities that diamond alone cannot provide. Here, we demonstrate heterogeneous integration of a thin-film lithium niobate (TFLN) platform, which has strong chi-2 nonlinearity and electro-optic effects, with thin diamond films. We demonstrate high-Q diamond photonic crystal cavities (Q factors exceeding 5x10^4 at 735 nm) that are lithographically aligned with TFLN photonic backbone and critically coupled to it. This allows us to realize low-loss diamond-TFLN "escalators" (loss ~1 dB/coupler) that support efficient light transfer between them. At cryogenic temperatures (5K), we can collect photons emitted from silicon vacancies (SiVs) embedded within the diamond structure via the TFLN photonic circuit. This approach establishes a scalable route toward integrated photonic circuits for practical quantum networking and other technologies.

Birgit J. M. Hausmann, İrfan Bulu, Vivek Venkataraman +2 more

Lin Jin, Wolfram H. P. Pernice