Enhanced Extraction of Silicon-Vacancy Centers Light Emission Using Bottom-Up Engineered Polycrystalline Diamond Photonic Crystal Slabs

Abstract

Silicon vacancy (SiV) centers are optically active defects in diamond. The SiV centers, in contrast to nitrogen vacancy (NV) centers, possess narrow and efficient luminescence spectrum (centered at ≈738 nm) even at room temperature, which can be utilized for quantum photonics and sensing applications. However, most of light generated in diamond is trapped in the material due to the phenomenon of total internal reflection. In order to overcome this issue, we have prepared two-dimensional photonic crystal slabs from polycrystalline diamond thin layers with high density of SiV centers employing bottom-up growth on quartz templates. We have shown that the spectral overlap between the narrow light emission of the SiV centers and the leaky modes extracting the emission into almost vertical direction (where it can be easily detected) can be obtained by controlling the deposition time. More than 14-fold extraction enhancement of the SiV centers photoluminescence was achieved compared to an uncorrugated sample. Computer simulation confirmed that the extraction enhancement originates from the efficient light-matter interaction between light emitted from the SiV centers and the photonic crystal slab.

Nanosphere Lithography for Structuring Polycrystalline Diamond Films

“…Various traditional and interesting size-and shape-tuneable features (e.g., spherical, ellipsoidal, pyramidal structures with various surface roughening) were easily and successfully obtained. The nanostructure's design, geometry, and dimension can be estimated by computer simulations for the targeted applications [3,29]. For example, in the case of hole fabrication, it is possible to achieve structures with various thickness (defined by the thickness of the deposited diamond film), hole periodicity (defined by the initial diameter of the spheres), hole diameter (defined by the plasma etching of the PS spheres), and hole depth (defined by the plasma etching of the diamond film).…”

“…[1]. These factors make it desirable for several technological applications in diverse fields of science and technology (e.g., optical, photonic, plasmonic devices, metamaterials, sensing applications) [2,3]. The applicability of diamond depends on its bulk and surface characteristics.…”

“…Reactive ion plasma etching (e.g., capacitively or inductively coupled plasma) through a mask is the most common and most useful structuring technique [5]. The masks are usually created and/or structured using conventional lithographic techniques (such as optical, electron-beam, ion-beam, laser interference, X-ray lithography) [3,6,7]. Patterning with unconventional lithographic techniques (e.g., nanosphere lithography, nanoimprinting, soft lithography) can also be applied to fabricate various micro-and nanostructured diamond films [8][9][10].…”

“…For diamond etching, RIE process (Phantom III, Trion Technology, Clearwater, FL, USA) was used [3]. The etching profiles were tuned using the input process parameters [28].…”

Two-dimensional photonic crystals increasing vertical light emission from Si nanocrystal-rich thin layers

“…Typically, electron beam lithography in combination with etching [14] or focused ion beam milling [15] are used to prepare photonic structures with well-defined dimensions on small areas. These approaches are therefore suitable for laboratory testings but not for practice.…”