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A novel approach to significantly enhance and comprehensively assess the level of nanochannel ordering in self-assembled nanoporous membranes is proposed and tested. An advanced technique based on a two-step anodization and two-step chemical treatment was used to prepare the perfect through membranes by opening channels from the bottom via electrochemical enlargement, and chemical removal of a residual metal and barrier alumina layer. The influence of the process parameters on the self-assembled ordering was studied, and various methods of order assessment were proposed and tested, such as distributions of equivalent disc radii, 2D Fourier transformations, autocorrelation, Hough transformations, Minkowski connectivity, and distributions of nanochannel centre positions. We have demonstrated that self-assembled ordering in nanoscaled membranes could be efficiently tuned by the process parameters, and different assessment methods should be used to comprehensively characterize the order of nanochannels in the nanoporous membranes. To demonstrate the potential of this technique, we show simulations of the narrowing of plasmon spectra in these materials. The proposed fabrication and assessment methods could be used to drastically enhance the properties of nanoporous membranes for nanoelectronics, filters, sensors, bio-active devices and other advanced emerging applications. Finally, our approach could be used for enhancing and tailoring other self-assembled systems and devices of considerable complexity.

Copyright © 2018 American Chemical Society. Single crystal diamond membranes that host optically active emitters are highly attractive components for integrated quantum nanophotonics. In this work we demonstrate bottom-up synthesis of single crystal diamond membranes containing germanium vacancy (GeV) color centers. We employ a lift-off technique to generate the membranes and perform chemical vapor deposition in the presence of a germanium source to realize the in situ doping. Finally, we show that these membranes are suitable for engineering of photonic resonators such as microdisk cavities with quality factors of ∼1500. The robust and scalable approach to engineer single crystal diamond membranes containing emerging color centers is a promising pathway for the realization of diamond integrated quantum nanophotonic circuits on a chip.

© 2018 The Royal Society of Chemistry. Single crystal, nanoscale diamond membranes are highly sought after for a variety of applications including nanophotonics, nanoelectronics and quantum information science. However, so far, the availability of conductive diamond membranes has remained an unreachable goal. In this work we present a complete nanofabrication methodology for engineering high aspect ratio, electrically active single crystal diamond membranes. The membranes have large lateral directions, exceeding ∼500 × 500 μm2 and are only several hundreds of nanometers thick. We further realize vertical single crystal p-n junctions made from the diamond membranes that exhibit onset voltages of ∼10 V and a current of several mA. Moreover, we deterministically introduce optically active color centers into the membranes, and demonstrate for the first time a single crystal nanoscale diamond LED. The robust and scalable approach to engineer the electrically active single crystal diamond membranes offers new pathways for advanced nanophotonic, nanoelectronic and optomechanical devices employing diamond.

© 2019 Optical Society of America Single-photon sources in solid-state systems are widely explored as fundamental constituents of numerous quantum-based technologies. We report the observation of single-photon emitters in zinc sulfide and present their photo-physical properties via established spectroscopy techniques. The emitter behaves like a three-level system with an intermediate metastable state. It emits at ∼640 nm, and its emission is linearly polarized, with a lifetime of (2.2 ± 0.8) ns. The existence of single-photon sources in zinc sulfide is appealing due to the well-established manufacturing techniques of the material, its versatile technological uses, as well as the availability of many zinc isotopes with potential for designing ad hoc emitter–host pairs with tailored properties.

© The Royal Society of Chemistry 2015. Fluorescent nanodiamonds are attracting major attention in the field of bio-sensing and bio-labeling. In this work we demonstrate a robust approach to achieve an encapsulation of individual nanodiamonds with phenol-ionic complexes that enhance the photoluminescence from single nitrogen vacancy (NV) centers. We show that single NV centres in the coated nanodiamonds also exhibit shorter lifetimes, opening another channel for high resolution sensing. We propose that the nanodiamond encapsulation reduces the non-radiative decay pathways of the NV color centers. Our results provide a versatile and assessable way to enhance photoluminescence from nanodiamond defects that can be used in a variety of sensing and imaging applications.