Individual color centers in diamond are promising for near-term quantum technologies including quantum key distribution and metrology. Here we show fabrication of a new color center which has photophysical properties surpassing those of the two main-stay centers, namely the nitrogen vacancy and NE8 centers. The new center is fabricated using focused ion beam implantation of nickel into isolated chemical vapor deposited diamond micro-crystals. Room temperature photoluminescence studies reveal a narrow emission in the near infrared region centered at 768 nm with a lifetime as short as 2 ns. Its focused ion beam compatibility opens the prospect to fabrication with nanometer resolution and realization of integrated quantum photonic devices. Preliminary investigations suggest that this center arises from an as-yet uncharacterized nickel-silicon complex.
Individual color centers in diamond are promising for near-term quantum technologies including quantum key distribution and metrology. Here we show fabrication of a new color center which has photophysical properties surpassing those of the two main-stay centers, namely the nitrogen vacancy and NE8 centers. The new center is fabricated using focused ion beam implantation of nickel into isolated chemical vapor deposited diamond micro-crystals. Room temperature photoluminescence studies reveal a narrow emission in the near infrared region centered at 768 nm with a lifetime as short as 2 ns. Its focused ion beam compatibility opens the prospect to fabrication with nanometer resolution and realization of integrated quantum photonic devices. Preliminary investigations suggest that this center arises from an as-yet uncharacterized nickel-silicon complex.
Individual color centers in diamond are promising for near-term quantum technologies including quantum key distribution and metrology. Here we show fabrication of an as-yet uncharacterized nickel-related complex in diamond which has photophysical properties surpassing the two main-stay centers for single-photon applications, namely, the nitrogen-vacancy and the nickel-nitrogen complex (NE8) center. This center was fabricated using focused ion-beam implantation of nickel into isolated chemical vapor-deposited diamond crystals. A possible correlation of the center to a Ni/Si complex is substantiated by a coimplantation of Ni and Si into a pure bulk diamond. Room-temperature photoluminescence studies reveal a narrow emission in the near infrared region centered at 768 nm with a lifetime as short as 2 ns.
Single-photon sources represent a key enabling technology in quantum optics, and single color centers in diamond are a promising platform to serve this purpose, due to their high quantum efficiency and photostability at room temperature. The widely studied nitrogen-vacancy (NV) centers are characterized by several limitations, thus other defects have recently been considered, with a specific focus of centers emitting in the near-infra red (NIR). In the present work, we report on the coupling of native NIR-emitting centers in high-quality single-crystal diamond with solid immersion lens (SIL) structures fabricated by focused ion beam (FIB) lithography. The reported improvements in terms of light collection efficiency make the proposed system an ideal platform for the development of single-photon emitters with appealing photophysical and spectral properties.
Quantum communication and quantum metrology established a demand for an accessible solid state systems which can generate a stream of single photons on demand [1]. Although single photon emission has been demonstrated from quantum dots (QD)[1,2], single molecules [3] and nanowires [4], their practical operation is limited by the temperature or photostability. Diamond crystals, however, are the most promising platform for generation of robust, photo-stable, single photons at room temperature [5,6]. Nevertheless, out of more than 500 existing optical centers in diamond only three known centers demonstrated a clear single photon emission: the nitrogen-vacancy complex [6,7], the silicon-vacancy complex [8] and the nickel-nitrogen complex [9,10]. Recent progress in materials science and fabrication techniques of diamond color centers unveiled novel quantum emitters with photo-physical properties surpassing the current mainstream [11,12,13]. Consequently, the versatility of the diamond lattice to host various impurities which give luminescence signals lead to a dramatic discovery of ultra bright single photon emitters operating in the MHz regime [14]. These new centers, comparable with QD in terms of brightness [1], but have the tremendous advantage of their room temperature operation and photo-stability. Furthermore, it opened a new avenue to investigate essentially an unknown group of single photon emitters. A brief description of the fabrication methods and a detailed quantum optical characterization of this class of diamond emitters is the subject of this presentation. In particular we will present the photo-physical properties of a novel family of single photon emitters, most likely originated from Cr impurities within the chemical vapor deposition grown nano-diamond crystals. We concentrate on the typical emission lines in the range of 740 - 790 nm, which exhibit single photon emission with count rate in the range of 0.8-3.2 106 counts/s at the limit of infinite optical excitation power, and life time as short as 1 ns. Even more, some of the emitters exhibit a photon statistics without any photon bunching, indicating a two-level system with unitary quantum efficiency. We will also show preliminary results of a resonant excitation at 4 K. We will highlight future directions to optimize these sources and avenues to investigate the fundamental properties of these centers.
Single photon emitters are core components of quantum technologies. In this work new family of emitters based on chromium impurities in diamond is presented. The emitters can be fabricated by ion implantation of chromium into bulk diamond or incorporated during the growth of diamond nanocrystals. The remarkable photo‐physical properties of these emitters include room temperature operation, narrow photoluminescence (PL) in the near infra red and ultra bright, fully polarized photon emission with count rate of 3.2×106 counts/s. These photo physical properties make the Cr centers ideal for quantum information processing, metrology, and cellular bio markers applications.
We demonstrate the coupling of single color centers in diamond to plasmonic and dielectric photonic structures to realize novel nanophotonic devices. Nanometer spatial control in the creation of single color centers in diamond is achieved by implantation of nitrogen atoms through high-aspect-ratio channels in a mica mask. Enhanced broadband single-photon emission is demonstrated by coupling nitrogen-vacancy centers to plasmonic resonators, such as metallic nanoantennas. Improved photon-collection efficiency and directed emission is demonstrated by solid immersion lenses and micropillar cavities. Thereafter, the coupling of diamond nanocrystals to the guided modes of micropillar resonators is discussed along with experimental results. Finally, we present a gas-phase-doping approach to incorporate color centers based on nickel and tungsten, in situ into diamond using microwave-plasma-enhanced chemical vapor deposition. The fabrication of silicon-vacancy centers in nanodiamonds by microwave-plasma-enhanced chemical vapor deposition is discussed in addition.
We present a detailed study of photophysical properties of single color centers in natural diamond samples emitting in the near infrared under optical excitation. Photoluminescence of these single emitters has several striking features, including narrow-band (FWHM 2 nm) fully polarized emission around 780 nm, a short excited-state lifetime of about 2 ns, and perfect photostability at room temperature under our excitation conditions. Development of a triggered single-photon source relying on this single color center is discussed for application to quantum key distribution.