1,720,961 research outputs found
The Lightwave Programme and Roadshow: An Overview and Update
No full textWhile optics and photonics are exciting disciplines with much research, industrial, and economic potential in the 21st century, this appreciation is only shared by a limited number of science, technology, engineering, and mathematics (STEM) experts, and there is a recognized STEM skills shortage. To widen the pool of talent, it is essential to expose students to optics and photonics throughout their education and particularly starting at a young age. The Lightwave programme, consisting of an interactive collection of photonics demonstrations and experiments targeted for primary school students, was thus created to facilitate this endeavor. The programme is run by doctoral students forming a team of “Lightwave ambassadors”. All the demonstrations that comprise Lightwave can be easily integrated into a physics curriculum, enabling educators to generate more student interest and enhance the image of science through an interactive pedagogy. We provide a description of the programme at its initial inception, and report on the recent additions and updates that have brought about its success, moving from a purely outreach driven focus to engaging pupils with our own research. We also discuss our approach to ensuring that our team of ambassadors are from diverse backgrounds and use both male and female students as role models. Finally, we reflect on how evaluation methods to obtain feedback from our activities are key to Lightwave's sustainability and in improving the perception of optics and photonics
45° tilted gratings for silica-based integrated polarizers
No full textWe report a novel study and demonstration of a broadband tilted grating-based integrated polarizer on a silica platform and demonstrate a polarisation extinction ratio of 4.9±0.4dB and operation in the C-band
Integrated optical circuits for quantum information processing
No full textIntegrated optical waveguide circuits are becoming increasingly important in quantum information processing. They provide a platform that is scaleable to multiple qubits, offers stability over the timescales required for multiple photon coincidence based measurements, and by utilizing telecommunications sources and hardware, allows low-loss and efficient operation. This work will present recent results and indicate research directions that are leading towards the demonstration of the required range of functions on chip, particularly on chip, sources, system tomography, phase control operations and detection
At the cross-roads of effective quantum information processing with integrated optical gates
No full textThe use of a silica integrated optical platform developed for the telecoms industry is allowing demonstrations of quantum operations with single photons and Bragg gratings that are challenging notions of classical computing. Operations such as Boson Sampling, number resolving photon detection at 1550nm, quantum teleportation and non-classical interferometry will be reported
Fabrication of silica-integrated waveguide circuits for quantum-enhanced sensing, quantum information processing, and number-resolving detection
No full textIntegrated optics is becoming increasingly important for applications in quantum information processing, quantum sensing and for advanced measurement. Intrinsically stable and low-loss it provides essential routing and coupling for quantum optical experiments offering functions such as interconnects, couplers, phase delays and routing. Silica-on-silicon has particular attractions, and in this work the fabrication approaches and advantages of the technique will be explored. In particular, UV direct writing of waveguides and Bragg gratings proves useful for its rapid-prototyping capability and its ability to provide grating for characterization of components for loss, birefringence and coupling ratio. This review concentrates on the fabrication of planar waveguide devices, and ways in which direct UV writing provides important functionality. Examples of applications of silica-on-silicon waveguides include quantum enhanced interferometry, teleportation, boson sampling as well as hybrid operation for single photon detection with transition edge sensors directly placed onto waveguide devices
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
High-birefringence direct-UV-written silica waveguides for heralded single-photon sources at telecom wavelengths
No full textWe present design, fabrication and characterization of direct-UV-written silica-on-silicon waveguides using novel silicate glasses made by flame hydrolysis deposition. We report waveguide birefringence from 5.24 ± 0.18×10-4 to 5.79 ± 0.10×10-4 suitable for heralded single-photon sources at telecom wavelengths
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