from single photon producing nitrogenvacancy (NV) color centers consisting of a substitutional nitrogen atom next to a vacancy that is engineered artificially in the diamond lattice. The nanoscale effects related to artificially engineered NV color centers attracted important attention to diamond due to applications ranging from quantum computing to cell imaging. [2][3][4] The luminescence from NV centers is extremely stable without any photobleaching or photoblinking [5][6][7] and compared to better known quantum dots, ND brings additional advantages such as high biocompatibility [8,9] and simple C-surface chemistry. [10,11] This allows grafting of biomolecules that are interesting for cellular targeting [12,13] or biomolecular drug delivery. [14][15][16] However, for very small ND particles (5 nm) blinking of NV centers was observed, [17] showing that the surface effects are of importance for stabilization of NV luminescence properties.Here we describe how the surface chemistry effects can make the ND bulk luminescence sensitive to chemical processes ongoing at the ND surface, with the aim of using ND for monitoring a chemical environment such as surface charges or pH, cellular DNA/RNA hybridization, interaction with cell receptors, etc. The proposed method is based on the control of an electronic chemical potential at the

Fluorescent cellular biomarkers play an essential role in biology and medicine for in vitro and in vivo imaging in living cells. Recently, we have demonstrated that photoluminescence (PL) can be driven chemically by changing the occupation of NV− and NV0 states by H‐ or O‐termination. In the presented work we study, how the luminescence of NV centers at controlled depth from the surface changes upon different surface treatment. We compare NV luminescence of hydrogen (H) and oxygen (O) terminated surfaces in single crystal diamond (SCD) containing shallow‐implanted NV centers (3–10 nm) with similarly treated nanodiamond particles (ND) of various size distributions. The H‐termination leads to reduction of NV− related luminescence in both, ND and SCD. The effect is much stronger in ND in comparison with SCD. We mathematically model both situations and discuss parameters influencing the effect, including implantation energy and different contents of nitrogen in the diamond crystal lattice.

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a b s t r a c tCharacteristic Raman features of boron-doped diamond layers with metallic conduction are studied experimentally and discussed in comparison with an extensive selection of literature data. Despite evidence that the main Raman bands are mostly characteristic features of carbon atom vibration modes, their position is found to be proportional to boron concentration. While the origin of the Raman bands located at c.a. 500 cm À1 remains unclear, the band centred at c.a. 1200 cm À1 is attributed to a maximum of phonon density of states due to softening of the Raman wave vector conservation rule. The downshift and broadening of the diamond line are attributed, primarily, to the domain size effect caused by scattering on boron impurities, secondly to the Fano effect due to electronic Raman interaction, and finally to lattice expansion due to the boron doping.

, et al.. Growth and characterization of nanodiamond layers prepared using the plasma-enhanced linear antennas microwave CVD system. Journal of Physics D: Applied Physics, IOP Publishing, 2010, 43 (37) Abstract. Industrial applications of PE CVD diamond grown on large area substrates, 3D shapes, at low substrate temperatures and on standard engineering substrate materials require novel plasma concepts. Based on the pioneering work of the group at AIST in Japan, highdensity coaxial delivery type of plasmas have been explored [1]. However, an important challenge is to obtain commercially interesting growth rates at very low substrate temperatures. In the presented work we introduce the concept of novel linear antenna sources, designed at Leybold Optics Dresden, using high-frequency pulsed MW discharge with a high plasma densitiy. This type of pulse discharges lead to the preparation of nanocrystalline diamond thin films, compared to ultra-nanocrystalline diamond thin films prepared in Ref [1]. We present OES data for the CH 4 -CO 2 -H 2 gas chemistry and we discuss the basic properties of the nanocrystalline diamond (NCD) films grown.

Lattice disorder, electronic Raman scattering, and Fano interaction effects are at the genesis of the Raman spectrum of heavily boron-doped diamond. However, no accurate unified description of this spectrum has been reported yet. In this work, we propose a novel analysis of the Raman spectrum of boron-doped diamond based on classical models of electronic Raman scattering and Fano effect. This new analysis shows that the Raman spectrum of boron-doped diamond results from the combination of electronic Raman scattering and its interaction, i.e. Fano effect, with the diamond phonon density of states and it confirms the 500 cm −1 and 1200 cm −1 bands originate from the phonon density of states.

Boron-doped nanocrystalline diamond (BDD) electrodes have recently attracted attention as materials for neural electrodes due to their superior physical and electrochemical properties, however their biocompatibility remains largely unexplored. In this work, we aim to investigate the in vivo biocompatibility of BDD electrodes in relation to conventional titanium nitride (TiN) electrodes using a rat subcutaneous implantation model. High quality BDD films were synthesized on electrodes intended for use as an implantable neurostimulation device. After implantation for 2 and 4 weeks, tissue sections adjacent to the electrodes were obtained for histological analysis. Both types of implants were contained in a thin fibrous encapsulation layer, the thickness of which decreased with time. Although the level of neovascularization around the implants was similar, BDD electrodes elicited significantly thinner fibrous capsules and a milder inflammatory reaction at both time points. These results suggest that BDD films may constitute an appropriate material to support stable performance of implantable neural electrodes over time.