70 research outputs found
On-chip generation of high-dimensional entangled quantum states and their coherent control
Optical quantum states based on entangled photons are essential for solving questions in fundamental physics and are at the heart of quantum information science1. Specifically, the realization of high-dimensional states (D-level quantum systems, that is, qudits, with D > 2) and their control are necessary for fundamental investigations of quantum mechanics2, for increasing the sensitivity of quantum imaging schemes3, for improving the robustness and key rate of quantum communication protocols4, for enabling a richer variety of quantum simulations5, and for achieving more efficient and error-tolerant quantum computation6. Integrated photonics has recently become a leading platform for the compact, cost-efficient, and stable generation and processing of non-classical optical states7. However, so far, integrated entangled quantum sources have been limited to qubits (D = 2)8, 9, 10, 11. Here we demonstrate on-chip generation of entangled qudit states, where the photons are created in a coherent superposition of multiple high-purity frequency modes. In particular, we confirm the realization of a quantum system with at least one hundred dimensions, formed by two entangled qudits with D = 10. Furthermore, using state-of-the-art, yet off-the-shelf telecommunications components, we introduce a coherent manipulation platform with which to control frequency-entangled states, capable of performing deterministic high-dimensional gate operations. We validate this platform by measuring Bell inequality violations and performing quantum state tomography. Our work enables the generation and processing of high-dimensional quantum states in a single spatial mode
Suppression of Parasitic Nonlinear Processes in Spontaneous Four-Wave Mixing with Linearly Uncoupled Resonators
We report on a signal-to-noise ratio characterizing the generation of identical photon pairs of more than 4 orders of magnitude in a ring resonator system. Parasitic noise, associated with single-pump spontaneous four-wave mixing, is essentially eliminated by employing a novel system design involving two resonators that are linearly uncoupled but nonlinearly coupled. This opens the way to a new class of integrated devices exploiting the unique properties of identical photon pairs in the same optical mode
Guideline Application in Real world: multi-Institutional Based survey of Adjuvant and first-Line pancreatic Ductal adenocarcinoma treatment in Italy. Primary analysis of the GARIBALDI survey
Background: Information about the adherence to scientific societies guidelines in the ‘real-world’ therapeutic management of oncological patients are lacking. This multicenter, prospective survey was aimed to improve the knowledge relative to 2017-2018 recommendations of the Italian Association of Medical Oncology (AIOM). Patients and methods: Treatment-naive adult patients with pancreatic adenocarcinoma were enrolled. Group A received adjuvant therapy, group B received primary chemotherapy, and group C had metastatic disease. The results on patients accrued until 31 October 2019 with a mature follow-up were presented. Results: Since July 2017, 833 eligible patients of 923 (90%) were enrolled in 44 Italian centers. The median age was 69 years (range 36-89 years; 24% >75 years); 48% were female; 93% had Eastern Cooperative Oncology Group (ECOG) performance status (PS) score of 0 or 1; group A: 16%, group B: 30%; group C: 54%; 72% Nord, 13% Center, 15% South. In group A, guidelines adherence was 68% [95% confidence interval (CI) 59% to 76%]; 53% of patients received gemcitabine and 15% gemcitabine + capecitabine; median CA19.9 was 29 (range 0-7300; not reported 15%); median survival was 36.4 months (95% CI 27.5-47.3 months). In group B, guidelines adherence was 96% (95% CI 92% to 98%); 55% of patients received nab-paclitaxel + gemcitabine, 27% FOLFIRINOX, 12% gemcitabine, and 3% clinical trial; median CA19.9 was 337 (range 0-20220; not reported 9%); median survival was 18.1 months (95% CI 15.6-19.9 months). In group C, guidelines adherence was 96% (95% CI 94% to 98%); 71% of patients received nab-paclitaxel + gemcitabine, 16% gemcitabine, 8% FOLFIRINOX, and 4% clinical trial; liver and lung metastases were reported in 76% and 23% of patients, respectively; median CA19.9 value was 760 (range 0-1374500; not reported 9%); median survival was 10.0 months (95% CI 9.1-11.1 months). Conclusions: The GARIBALDI survey shows a very high rate of adherence to guidelines and survival outcome in line with the literature. CA19.9 testing should be enhanced; nutritional and psychological counseling represent an unmet need. Enrollment to assess adherence to updated AIOM guidelines is ongoing
Candidate Interventions for Integrating Hypertension and Cardiovascular-Kidney-Metabolic Care in Primary Health Settings: HEARTS 2.0 Phase 1
Background: HEARTS in the Americas is the regional adaptation of the WHO Global HEARTS Initiative, aimed at helping countries enhance hypertension and cardiovascular disease (CVD) risk management in primary care settings. Its core implementation tool, the HEARTS Clinical Pathway, has been adopted by 28 countries. To improve the care of hypertension, diabetes, and chronic kidney disease (CKD), HEARTS 2.0 was developed as a three-phase process to integrate evidence-based interventions into a unified care pathway, ensuring consistency across fragmented guidelines. This paper focuses on Phase 1, highlighting targeted interventions to improve and update the HEARTS Clinical Pathway. Methods: First, the coordinating group defined the project’s scope, objectives, principles, methodological framework, and tools. Second, international experts from different disciplines proposed interventions to enhance the HEARTS Clinical Pathway. Third, the coordinating group harmonized these proposals into unique interventions. Fourth, experts appraised the appropriateness of the proposed interventions on a 1-to-9 scale using the adapted RAND/UCLA Appropriateness Method. Finally, interventions with a median score above 6 were deemed appropriate and selected as candidates to enhance the HEARTS Clinical Pathway. Results: Building on the existing HEARTS Clinical Pathway, 45 unique interventions were selected, including community-based screening, early detection and management of risk factors, lower blood pressure thresholds for diagnosing hypertension in high-CVD-risk patients, reinforcement of single-pill combination therapy, inclusion of sodium-glucose cotransporter-2 inhibitors for patients with diabetes, CKD, or heart failure, expanded roles for non-physician health workers in team-based care, and strengthened clinical documentation, monitoring, and evaluation. Conclusion: HEARTS 2.0 Phase 1 identifies key interventions to integrate and improve hypertension and cardiovascular-kidney-metabolic care within primary care, enabling their seamless incorporation into a unified and effective clinical pathway. This process will inform an update to the HEARTS Clinical Pathway, optimizing resources, reducing care fragmentation, improving care delivery, and advancing health equity, thereby supporting global efforts to combat the leading causes of death and disability
All-fibered chalcogenide based continuous-wave parametric amplification in the mid-infrared
We demonstrate parametric amplification around 2 μm in a dispersion engineered tapered microstructured chalcogenide fiber. Almost 5 dB of signal amplification was achieved by 125 mW coupled power from a thulium-doped fiber pump laser
Characterization and modeling of microstructured chalcogenide fibers for efficient mid-infrared wavelength conversion
We experimentally demonstrate wavelength conversion in the 2 micron region by four-wave mixing in an AsSe and a GeAsSe chalcogenide photonic crystal fibers. A maximum conversion efficiency of -25.4 dB is measured for 112 mW of coupled continuous wave pump in a 27 cm long fiber. We estimate the dispersion parameters and the nonlinear refractive indexes of the chalcogenide PCFs, establishing a good agreement with the values expected from simulations. The different fiber geometries and glass compositions are compared in terms of performance, showing that GeAsSe is a more suited candidate for nonlinear optics at 2 micron. Building from the fitted parameters we then propose a new tapered GeAsSe PCF geometry to tailor the waveguide dispersion and lower the zero dispersion wavelength (ZDW) closer to the 2 mu m pump wavelength. Numerical simulations shows that the new design allows both an increased conversion efficiency and bandwidth, and the generation of idler waves further in the mid-IR regions, by tuning the pump wavelength in the vicinity of the fiber ZDW
MIR supercontinuum in all-normal dispersion Chalcogenide photonic crystal fibers pumped with 2μm femtosecond laser
We demonstrate mid-infrared supercontinuum generation in an all-normal dispersion Chalcogenide PCF pumped by fiber laser. The -20dB bandwidth is 1.7~2.7μm dominated by self phase modulation and optical wave breaking. Tapering is proposed to improve performance
Observation of second harmonic and sum frequency in an optically poled Si3N4 waveguide
Enhanced second order nonlinear processes in a Si3N4 waveguide following optically induced χ(2) is demonstrated, enabling the detection of a frequency doubled pulsed train and SFG with > -37 dB conversion efficiency for 18 W pump peak power
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