Large-scale surface nanopatterning of a commercial silicon (Si) wafer in the form of regular 1D arrays of high-aspect-ratio vertical nanosheets (NSs) for antifouling and other potential promising optoelectronic, nanophotonic, and sensing applications was performed via multishot picosecond IRlaser ablation under a 5-mm-thick carbon disulfide liquid layer. Specifically, the nanopatterned surface layer demonstrates the broad ultralow mid-IR transmittance and the high content of sulfur, carbon, and even oxygen in the modified submicron-thick top layer, preventing the appearance of a Staphylococcus aureus bacterial biofilm. High-resolution transmission electron microscopy studies exhibit the anticorrelating inner versus outer surface abundance of donor sulfur versus adverse carbon and oxygen components and the amorphous structure of the sulfur-hyperdoped NSs atop their crystalline basements. These NSs indicate their appearance via the interfacial vapor/ plume bubble-mediated codeposition of Si ablation nanoplumes from the regular trenches and sulfur-containing products of carbon disulfide decomposition in the bubble. Numerical modeling indicates the nanoplasmonic origin of the Si NSs, self-limited in both the 100 nm periods and the submicron heights.

This article presents a new simple method of creating light-absorbing carbon material for optical devices such as bolometers. A simple method of laser microstructuring of graphene oxide is used in order to create such material. The absorption values of more than 98% in the visible and more than 90% in the infrared range are achieved. Moreover thermal properties of the films, such as temperature dependence and the thermal response of the samples, are studied. The change in resistance with temperature is 13 Ohm K, temperature coefficient of resistance (TCR) is 0.3% K, and the sensitivity is 0.17 V W at 300 K. Thermal conductivity is rather high at ∼104 W m K at 300 K. The designed bolometer operates at room temperature using incandescent lamp as a light source. This technique suggests a new inexpensive way to create a selective absorption coating and/or active layer for optical devices. Developed GO and rGO films have a large surface area and high conductivity. These properties make carbon coatings a perfect candidate for creating a new type of optoelectronic devices (gas sensors, detectors of biological objects, etc.).

Silicon-vacancy (SiV–) color center in diamond is of high interest for applications in nanophotonics and quantum information technologies, as a single photon emitter with excellent spectral properties. To obtain spectrally identical SiV– emitters, we doped homoepitaxial diamond films in situ with 28Si, 29Si, and 30Si isotopes using isotopically enriched (>99.9%) silane SiH4 gas added in H2–CH4 mixtures in the course of the microwave plasma-assisted chemical vapor deposition process. Zero-phonon line components as narrow as ∼4.8 GHz were measured in both absorption and luminescence spectra for the monoisotopic SiV– ensembles with a concentration of a few parts per billion. We determined with high accuracy the Si isotopic energy shift of SiV– zero-phonon line. The SiV– emission intensity is shown to be easily controlled by the doped epifilm thickness. Also, we identified and characterized the localized single photon SiV– sources. The developed doping process opens a way to produce the SiV– emitter ensembles with energy confined in an extremely narrow range.

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