Photonic-Cavity-Enhanced Laser Writing of Color Centers in Diamond.

Color centers in diamond have widespread utility in quantum technologies, but their creation process remains stochastic in nature. Deterministic creation of color centers in device-ready diamond platforms can improve the yield, scalability, and integration. Recent work using pulsed laser excitation has shown impressive progress in deterministically creating defects in bulk diamond. Here, we extend this laser-writing process into nanophotonic devices etched into diamond membranes, including nanopillars and photonic resonators with writing and subsequent readout occurring in situ at cryogenic temperatures. We demonstrate the optically driven creation of carbon vacancy (GR1) and nitrogen vacancy (NV) centers in diamond nanopillars and observe enhanced photoluminescence collection from them. We also fabricate bullseye resonators and leverage their cavity modes to locally amplify the laser-writing field, yielding defect creation with picojoule write-pulse energies 100 times lower than those typically used in bulk diamond demonstrations.

CYR61/CCN1: A novel mediator of redox response in corneal stromal cells of keratoconus.

Keratoconus (KC) is a progressive, multifactorial and ectatic corneal disorder that characterized by steepening thinning of the cornea. It was previously demonstrated that oxidative stress has a strong link with KC progression. However, the molecular mechanism underlying oxidative stress response in KC remains unclear. Hence, the present study analyzed the heterogeneity of response of corneal stromal cells (CSCs) to oxidative stress in order to further illustrate how oxidative shape the pathophysiology of KC. Single-cell transcriptomics analysis revealed that CSCs demonstrated significant higher oxidative stress score in the KC group compared to the Ctrl group. The expression of oxidative markers verified by experiments illustrated elevated oxidative stress levels and insufficient antioxidant levels in CSCs of KC. In further single-cell transcriptomics analysis, we identified CYR61 to distinguish different subgroups of CSCs responding to oxidative stress. The cornea stroma cells in KC could be differentiated into CYR61high cells and CYR61low cells. Of note, the CYR61high cells showed lower score in collagen production process and higher score in collagen catabolic process. Further experiments illustrated that CYR61 was elevated in KC and associated with collagen production.

Tunable and Transferable Diamond Membranes for Integrated Quantum Technologies.

Color centers in diamond are widely explored as qubits in quantum technologies. However, challenges remain in the effective and efficient integration of these diamond-hosted qubits in device heterostructures. Here, nanoscale-thick uniform diamond membranes are synthesized via "smart-cut" and isotopically (12C) purified overgrowth. These membranes have tunable thicknesses (demonstrated 50 to 250 nm), are deterministically transferable, have bilaterally atomically flat surfaces (Rq ≤ 0.3 nm), and bulk-diamond-like crystallinity. Color centers are synthesized via both implantation and in situ overgrowth incorporation. Within 110-nm-thick membranes, individual germanium-vacancy (GeV-) centers exhibit stable photoluminescence at 5.4 K and average optical transition line widths as low as 125 MHz. The room temperature spin coherence of individual nitrogen-vacancy (NV-) centers shows Ramsey spin dephasing times (T2*) and Hahn echo times (T2) as long as 150 and 400 µs, respectively. This platform enables the straightforward integration of diamond membranes that host coherent color centers into quantum technologies.

High-Q Nanophotonic Resonators on Diamond Membranes using Templated Atomic Layer Deposition of TiO2.

Integrating solid-state quantum emitters with nanophotonic resonators is essential for efficient spin-photon interfacing and optical networking applications. While diamond color centers have proven to be excellent candidates for emerging quantum technologies, their integration with optical resonators remains challenging. Conventional approaches based on etching resonators into diamond often negatively impact color center performance and offer low device yield. Here, we developed an integrated photonics platform based on templated atomic layer deposition of TiO2 on diamond membranes. Our fabrication method yields high-performance nanophotonic devices while avoiding etching wavelength-scale features into diamond. Moreover, this technique generates highly reproducible optical resonances and can be iterated on individual diamond samples, a unique processing advantage. Our approach is suitable for a broad range of both wavelengths and substrates and can enable high-cooperativity interfacing between cavity photons and coherent defects in diamond or silicon carbide, rare earth ions, or other material systems.

Pharmacokinetics and Tissue Distribution of Gingerols and Shogaols from Ginger (Zingiber officinale Rosc.) in Rats by UPLC⁻Q-Exactive⁻HRMS.

Gingerols and shogaols are recognized as active ingredients in ginger and exhibit diverse pharmacological activities. The preclinical pharmacokinetics and tissue distribution investigations of gingerols and shogaols in rats remain less explored, especially for the simultaneous analysis of multi-components. In this study, a rapid, sensitive, selective, and reliable method using an Ultra-Performance Liquid Chromatography Q-Exactive High-Resolution Mass Spectrometer (UPLC-Q-Exactive⁻HRMS) was established and validated for simultaneous determination of eight compounds, including 6-gingerol, 6-shogaol, 8-gingerol, 8-shogaol, 10-gingerol, 10-shogaol, Zingerone, and 6-isodehydrogingenone in plasma and tissues of rats. The analytes were separated on a Syncronis C18 column (100 × 2.1 mm, 1.7 µm) using a gradient elution of acetonitrile and 0.1% formic acid in water at a flow rate of 0.25 mL/min at 30 °C. The method was linear for each ingredient over the investigated range with all correlation coefficients greater than 0.9910. The lowest Lower Limit of quantitation (LLOQ) was 1.0 ng/mL. The intra- and inter-day precisions (Relative Standard Deviation, RSD%) were less than 12.2% and the accuracy (relative error, RE%) ranged from -8.7% to 8.7%. Extraction recovery was 91.4⁻107.4% and the matrix effect was 86.3⁻113.4%. The validated method was successfully applied to investigate the pharmacokinetics and tissue distribution of eight components after oral administration of ginger extract to rats. These results provide useful information about the pharmacokinetics and biodistribution of the multi-component bioactive ingredients of ginger in rats and will contribute to clinical practice and the evaluation of the safety of a Chinese herbal medicine.

High-Q cavity interface for color centers in thin film diamond.

Quantum information technology offers the potential to realize unprecedented computational resources via secure channels distributing entanglement between quantum computers. Diamond, as a host to optically-accessible spin qubits, is a leading platform to realize quantum memory nodes needed to extend such quantum links. Photonic crystal (PhC) cavities enhance light-matter interaction and are essential for an efficient interface between spins and photons that are used to store and communicate quantum information respectively. Here, we demonstrate one- and two-dimensional PhC cavities fabricated in thin-film diamonds, featuring quality factors (Q) of 1.8 × 105 and 1.6 × 105, respectively, the highest Qs for visible PhC cavities realized in any material. Importantly, our fabrication process is simple and high-yield, based on conventional planar fabrication techniques, in contrast to the previous with complex undercut processes. We also demonstrate fiber-coupled 1D PhC cavities with high photon extraction efficiency, and optical coupling between a single SiV center and such a cavity at 4 K achieving a Purcell factor of 18. The demonstrated photonic platform may fundamentally improve the performance and scalability of quantum nodes and expedite the development of related technologies.

Direct-bonded diamond membranes for heterogeneous quantum and electronic technologies.

Diamond has superlative material properties for a broad range of quantum and electronic technologies. However, heteroepitaxial growth of single crystal diamond remains limited, impeding integration and evolution of diamond-based technologies. Here, we directly bond single-crystal diamond membranes to a wide variety of materials including silicon, fused silica, sapphire, thermal oxide, and lithium niobate. Our bonding process combines customized membrane synthesis, transfer, and dry surface functionalization, allowing for minimal contamination while providing pathways for near unity yield and scalability. We generate bonded crystalline membranes with thickness as low as 10 nm, sub-nm interfacial regions, and nanometer-scale thickness variability over 200 by 200 µm2 areas. We measure spin coherence times T2 for nitrogen vacancy centers in 150 nm-thick bonded membranes of up to 623 ± 21 µs, suitable for advanced quantum applications. We demonstrate multiple methods for integrating high quality factor nanophotonic cavities with the diamond heterostructures, highlighting the platform versatility in quantum photonic applications. Furthermore, we show that our ultra-thin diamond membranes are compatible with total internal reflection fluorescence (TIRF) microscopy, which enables interfacing coherent diamond quantum sensors with living cells while rejecting unwanted background luminescence. The processes demonstrated herein provide a full toolkit to synthesize heterogeneous diamond-based hybrid systems for quantum and electronic technologies.

Eye Rubbing in Chinese Patients With Keratoconus: A Multicenter Analysis.

PURPOSE: To investigate the eye rubbing habits of Chinese patients with keratoconus. METHODS: This study was carried out from 2018 to June 2022 at Shandong Eye Hospital, Qingdao Eye Hospital, and Henan Eye Hospital. The study compared the number of patients who rubbed their eyes between medical records and second time questionnaires, eye rubbing of patients with myopia and patients with keratoconus, and disease severity between patients with keratoconus. A questionnaire survey of ophthalmologists was conducted to determine their degree of awareness that eye rubbing is a risk factor for keratoconus. RESULTS: The study assessed 799 patients with keratoconus and 798 control patients, and 97 ophthalmologists. The average proportion of patients with keratoconus who rubbed their eyes was 31.0% in the medical records with an increasing trend related to the increase in ophthalmologists' awareness, 66.6% after the second follow-up, and 25.4% among patients with myopia. After multivariate analysis, the following variables showed significant results: eye rubbing frequency more than 10 times/day (odds ratio [OR], 9.168; P < .001); rubbing with knuckles (OR, 9.804; P = .001); and prone sleep position (OR, 12.427; P < .001). The proportion of patients who rubbed their eyes with stage IV keratoconus was 71.9%, 18.9% higher than those with stage I, 4.8% higher than stage II, and 17.8% higher than stage III. CONCLUSIONS: The proportion of Chinese patients with keratoconus who rubbed their eyes was relatively high. The main reasons for the low proportions reported were lack of attention. Clinical attention should be paid to eye rubbing in patients with keratoconus who should be educated to avoid it. [J Refract Surg. 2023;39(10):712-718.].