Low‐Temperature Silicon‐Vacancy Luminescence of Individual Chemical Vapor Deposition Nanodiamonds Grown by Seeding and Spontaneous Nucleation
Dmitrii G. Pasternak, Jibo Dai, Dmitry A. Kalashnikov, Vadim Sedov, Мартьянов Артём Константинович, Victor Ralchenko, Leonid A. Krivitsky, Igor I. Vlasov
Diamond nanoparticles with optically active color centers can be used in nanoscale devices for quantum networking and sensing. A particular interest is focused on nanodiamonds (NDs) containing a small ensemble of negatively charged silicon‐vacancy (SiV) centers. Such NDs can be integrated with on‐chip optical structures. Here, chemical vapor deposition (CVD) is used to synthesize diamond particles of less than 100 nm in size containing 10–20 centers per ND. Two types of NDs grown on a Si substrate are studied, seeded with detonation NDs and without any seeding. The SiV luminescence under off‐resonant and resonant laser excitation at the temperature of 15 K is investigated. The emission lines of SiVs of individual NDs are well resolved and found to be spread in the range of 730–750 nm. The typical SiV linewidth is within 1–2 GHz for spontaneous NDs, which is only a factor of 2.5–5 broader than the lifetime limited linewidth of the SiV at 15 K. The emission of a single SiV is highly stable for both types of samples. This work is a critical step toward the synthesis of SiVs suitable for the realization of integrated quantum photonic devices.
Diamond nanoparticles with optically active color centers can be used in nanoscale devices for quantum networking and sensing. A particular interest is focused on nanodiamonds (NDs) containing a small ensemble of negatively charged silicon‐vacancy (SiV) centers. Such NDs can be integrated with on‐chip optical structures. Here, chemical vapor deposition (CVD) is used to synthesize diamond particles of less than 100 nm in size containing 10–20 centers per ND. Two types of NDs grown on a Si substrate are studied, seeded with detonation NDs and without any seeding. The SiV luminescence under off‐resonant and resonant laser excitation at the temperature of 15 K is investigated. The emission lines of SiVs of individual NDs are well resolved and found to be spread in the range of 730–750 nm. The typical SiV linewidth is within 1–2 GHz for spontaneous NDs, which is only a factor of 2.5–5 broader than the lifetime limited linewidth of the SiV at 15 K. The emission of a single SiV is highly stable for both types of samples. This work is a critical step toward the synthesis of SiVs suitable for the realization of integrated quantum photonic devices.
Abstract Diamond color centers have been widely studied in the field of quantum optics. The negatively charged silicon vacancy (SiV − ) center exhibits a narrow emission linewidth at the wavelength of 738 nm, a high Debye–Waller factor, and unique spin properties, making it a promising emitter for quantum information technologies, biological imaging, and sensing. In particular, nanodiamond (ND)‐based SiV − centers can be heterogeneously integrated with plasmonic and photonic nanostructures and serve as in vivo biomarkers and intracellular thermometers. Out of all methods to produce NDs with SiV − centers, ion implantation offers the unique potential to create controllable numbers of color centers in preselected individual NDs. However, the formation of single color centers in NDs with this technique has not been realized. We report the creation of single SiV − centers featuring stable high‐purity single‐photon emission through Si implantation into NDs with an average size of ∼20 nm. We observe room temperature emission, with zero‐phonon line wavelengths in the range of 730–800 nm and linewidths below 10 nm. Our results offer new opportunities for the controlled production of group‐IV diamond color centers with applications in quantum photonics, sensing, and biomedicine.
Nanodiamonds containing color centers have been attracting attention as a hybrid system with nanophotonic devices to realize photonic quantum information devices such as highly efficient single photon sources. In various color centers, silicon vacancy (SiV) centers are especially interesting because of high photo-stability, high brightness, high Debye-Waller factor (about 70%), and lifetime-limited fluorescence linewidth. The nanodiamonds containing SiV centers have been usually fabricated by milling large nanodiamonds with SiV centers, which are synthesized by chemical vapor deposition (CVD). However, this milling method has an issue with the production yield. Here, we report on the fabrication of SiV centers inside nanodiamonds by direct implantation of Si ions, which allows the creation at a high production yield due to no requirement of the milling process. By implanting Si ions into nanodiamonds (median size of 25 nm), we fabricate SiV centers exhibiting a narrow linewidth of about 7 nm at room temperature. This linewidth is more than twice as narrow as previous reports on the implantation of Si ions into nanodiamonds.
Color centers in diamond are versatile solid state atomic-like systems suitable for quantum technological applications. In particular, the negatively charged silicon vacancy center (SiV) exhibits a narrow photoluminescence (PL) line and lifetime-limited linewidth in a bulk at cryogenic temperature. We present a low-temperature study of chemical vapour deposition (CVD)-grown diamond nano-pyramids containing SiV centers. The PL spectra feature a bulk-like zero-phonon line with ensembles of SiV centers, with a linewidth below 10 GHz which demonstrates very low crystal strain for such a nano-object.
Silicon-vacancy (SiV) color centers in diamond offer a promising system for quantum information applications owing to their intense narrowband emission and optically detectable spin states. Here, the fluorescent properties of ensembles and single SiV centers in diamonds obtained by high-pressure high-temperature synthesis from adamantane (below referred to as adamantane diamonds) are investigated at liquid-helium temperatures. Ensembles of SiV centers (~10 3 ) are studied in large diamond crystals (1–2 µm in size). Despite the large number of excited centers, the fine structure of the zero-phonon line, corresponding to four allowed optical transitions between the ground- and excited-state doublets of the SiV center, can be observed in the fluorescence spectra of these crystals. The width of individual lines is in the range of 60–80 GHz, which is explained by their inhomogeneous broadening. Single SiV centers are studied in diamond crystallites with sizes of about 200 nm. The width of the narrowest transition lines observed in the fluorescence spectra of single SiV centers under resonant excitation is almost three orders of magnitude smaller than linewidths in the spectra of SiV ensembles and is as small as 94 MHz; i.e., these lines are so narrow that their width is determined by the lifetime of the upper state of the transition. Therefore, adamantane nanodiamond features the narrowest emission line width of a single SiV center at cryogenic temperatures among other types of SiV-con-taining nanodiamonds of similar sizes obtained by the high-pressure high-temperature and chemical vapor deposition techniques.
Abstract Silicon vacancy (SiV) centers in diamonds have attracted much attention because of their stability and narrow emission linewidth, and are promising for applications in quantum information technology. SiV-center-encapsulated nanodiamonds have also attracted much attention because of their potential to be coupled to various photonic devices. One efficient way to fabricate nanodiamonds that contain SiV centers is Si ion implantation into nanodiamonds. However, the evaluation of a single SiV center in a nanodiamond produced by this method at low temperatures has not been performed. In this study, we report on the optical properties of a single SiV center in a nanodiamond produced by ion implantation at cryogenic temperatures. The emission spectrum from a single SiV center ( g 2 ( 0 ) = 0.19 ) was observed with four distinct fine splittings of the zero-phonon line (ZPL) at 4 K. At an excitation power of 50 μ W, the full width at half maximum of the ZPL reached the spectrometer resolution limit (0.09 nm). The temperature dependence of the emission peak is consistent with that of the emission coming from an SiV center under high strain. The results obtained in this work suggest that nanodiamonds containing single SiV centers formed using this method will be an important building block for the realization of quantum information applications.
Ultrasmall (about 10 nm), low-strain, artificially produced diamonds with an internal, active color center have substantial potential for quantum information processing and biomedical applications. Thus, it is of great importance to be able to artificially produce such diamonds. Here, we report on the high-pressure, high-temperature synthesis of such nanodiamonds about 10 nm in size and containing an optically active, single silicon-vacancy color center. Using special sample preparation technique, we were able to prepare samples containing single nanodiamonds on the surface. By correlating atomic-force microscope images and confocal optical images, we verified the presence of optically active color centers in single nanocrystals, and using second-order correlation measurements, we proved the single-photon emission statistics of these nanodiamonds. These color centers have nonblinking, spectrally narrow emission with narrow distribution of spectral width and positions of zero-phonon line, thus proving the high quality of the nanodiamonds produced.