1,003 research outputs found
Template-assisted bottom-up growth of nanocrystalline diamond micropillar arrays
No full text Micro-patterned diamond has been investigated for numerous applications, such as biomimetic surfaces, electrodes for cell stimulation and energy storage, photonic structures, imprint lithography, and others. Controlled patterning of diamond substrates and moulds typically requires lithography-based top-down processing, which is costly and complex. In this work, we introduce an alternative, cleanroom-free approach consisting of the bottom-up growth of nanocrystalline diamond (NCD) micropillar arrays by chemical vapour deposition (CVD) using a commercial porous Si membrane as a template. Conformal pillars of ~4.7 μm in height and ~2.2 μm in width were achieved after a maximum growth time of 9 h by hot-filament CVD (2% CH 4 in H 2 , 725 °C at 10 mbar). In order to demonstrate one of many possible applications, micropillar arrays grown for 6 h, with ~2 μm in height, were evaluated as moulds for imprint lithography by replication onto hard cyclic olefin copolymer (COC) and onto soft polydimethylsiloxane (PDMS) elastomer. The results showed preserved mechanical integrity of the diamond moulds after replication, as well as full pattern transfer onto the two polymers, with matching dimensions between the grown pillars and the replicated holes. Prior surface treatment of the diamond mould was not required for releasing the PDMS replica, whereas the functionalisation of the diamond surface with a perfluorododecyltrichlorosilane (FDDTS) anti-stiction layer was necessary for the successful release of the COC replica from the mould. In summary, this paper presents an alternative and facile route for the fabrication of diamond micropillar arrays and functional micro-textured surfaces. Micro and Nano Engineerin
School Act from Mrs. Jeanette L. Court
No full textLetter - Legislation 1933-1935 - School Act from Mrs. Jeanette L. Court (Diamond City, AB)AWI collectio
Quantum Control of the Tin-Vacancy Spin Qubit in Diamond
No full textGroup-IV colour centres in diamond are a promising light-matter interface for quantum networking devices. We demonstrate multiaxis coherent control of the SnV spin-qubit via an all-optical stimulated Raman drive between the ground and excited states.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.QID/Hanson La
Diamond NV centers for quantum computing and quantum networks
No full textThe exotic features of quantum mechanics have the potential to revolutionize information technologies. Using superposition and entanglement, a quantum processor could efficiently tackle problems inaccessible to current-day computers. Nonlocal correlations may be exploited for intrinsically secure communication across the globe. Finding and controlling a physical system suitable for fulfi lling these promises is one of the greatest challenges of our time. The nitrogen-vacancy (NV) center in diamond has recently emerged as one of the leading candidates for such quantum information technologies thanks to its combination of atom-like properties and solid-state host environment. We review the remarkable progress made in the past years in controlling electrons, atomic nuclei, and light at the single-quantum level in diamond. We also discuss prospects and challenges for the use of NV centers in future quantum technologies.Quantum NanoscienceApplied Science
A hands-on activity to introduce the structure of NV-center quantum bits in diamond
No full textFor the start of a secondary school level lesson series on quantum computing, we designed a hands-on modeling activity where students construct a model diamond lattice with a nitrogen vacancy (NV) defect. NV centers find application as qubits and sensitive magnetometers. This activity aims to help students visualize the structure of such NV centers within the diamond lattice, making the subject matter more tangible. The activity has proven to be challenging but feasible. It features both collaborative and competitive elements thereby surely creating an energizing buzz in the classroom.Science & Engineering EducationScience Education and Communicatio
Strontium
No full text"Prepared by Syracuse Research Corporation under contract no. 205-1999-00024; prepared for U.S. Dept. of Health and Human Services, Public Health Service, Agency for Toxic Substances and Disease Registry."Chemical manager(s)/author(s): Alfred F. Dorsey, ATSDR, Division of Toxicology, Atlanta, GA; Margaret E. Fransen, Gary L. Diamond, Richard J. Amata, Syracuse Research Corporation, North Syracuse, NY.Includes bibliographical references (p. 277-365).205-1999-0002
Investigation of the Stark Effect on a Centrosymmetric Quantum Emitter in Diamond
No full textQuantum emitters in diamond are leading optically accessible solid-state qubits. Among these, Group IV-vacancy defect centers have attracted great interest as coherent and stable optical interfaces to long-lived spin states. Theory indicates that their inversion symmetry provides first-order insensitivity to stray electric fields, a common limitation for optical coherence in any host material. Here we experimentally quantify this electric field dependence via an external electric field applied to individual tin-vacancy (SnV) centers in diamond. These measurements reveal that the permanent electric dipole moment and polarizability are at least 4 orders of magnitude smaller than for the diamond nitrogen vacancy (NV) centers, representing the first direct measurement of the inversion symmetry protection of a Group IV defect in diamond. Moreover, we show that by modulating the electric-field-induced dipole we can use the SnV as a nanoscale probe of local electric field noise, and we employ this technique to highlight the effect of spectral diffusion on the SnV.QID/Hanson La
Current-induced nanogap formation and graphitization in boron-doped diamond films
No full textA high-current annealing technique is used to fabricate nanogaps and hybrid diamond/graphite structures in boron-doped nanocrystalline diamond films. Nanometer-sized gaps down to ?1?nm are produced using a feedback-controlled current annealing procedure. The nanogaps are characterized using scanning electron microscopy and electronic transport measurements. The structural changes produced by the elevated temperature, achieved by Joule heating during current annealing, are characterized using Raman spectroscopy. The formation of hybridized diamond/graphite structure is observed at the point of maximum heat accumulation.ChemE/Chemical EngineeringApplied Science
Nanopositioning of a diamond nanocrystal containing a single nitrogen-vacancy defect center
No full textPrecise control over the position of a single quantum object is important for many experiments in quantum science and nanotechnology. We report on a technique for high-accuracy positioning of individual diamond nanocrystals. The positioning is done with a home-built nanomanipulator under real-time scanning electron imaging, yielding an accuracy of a few nanometers. This technique is applied to pick up, move, and position a single nitrogen-vacancy (NV) defect center contained in a diamond nanocrystal. We verify that the unique optical and spin properties of the NV center are conserved by the positioning process.Kavli Institute of NanoscienceApplied Science
Two-Photon Quantum Interference from Separate Nitrogen Vacancy Centers in Diamond
No full textWe report on the observation of quantum interference of the emission from two separate nitrogen vacancy (NV) centers in diamond. Taking advantage of optically induced spin polarization in combination with polarization filtering, we isolate a single transition within the zero-phonon line of the nonresonantly excited NV centers. The time-resolved two-photon interference contrast of this filtered emission reaches 66%. Furthermore, we observe quantum interference from dissimilar NV centers tuned into resonance through the dc Stark effect. These results pave the way towards measurement-based entanglement between remote NV centers and the realization of quantum networks with solid-state spins.QN/Quantum NanoscienceApplied Science
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