Developing a Nanowriter System: Simulation and Experimental Set-Up of a Plasmonic-Based Lens Design

2006 ◽  
Vol 505-507 ◽  
pp. 1-6 ◽  
Author(s):  
Chih Kung Lee ◽  
C.L. Lin ◽  
D.Z. Lin ◽  
T.D. Cheng ◽  
Ching Kao Chang ◽  
...  

The aim of this article is to introduce a nanowriter system that could lead to a sub-micrometer spot size using a visible light source under ambient conditions. The key component of the system is a focusing optical head, which incorporates a plasmonic-based lens instead of a conventional lens. Based on knowledge of the physical origin of extraordinary transmission and directional beaming, we theorize that the directional beaming phenomenon can be explained simply as a surface plasmon (SP) diffraction along the corrugations as long as the multiple scattering effects are taken into account to modify the dispersion relationship of the surface plasmon. We introduce a Rigorous Coupled Wave Analysis (RCWA) formulation to pursue a precise dispersion relationship needed for the lens design. Comparing the resultant theoretical data between Finite Difference Time Domain (FDTD) simulations and RCWA results, we found good agreement and the many important characteristic parameters needed for an innovative lens design. We also set up a writing-test optomechanical system to examine the photoresist exposure ability of the plasmonic-based lens.

Micromachines ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 116
Author(s):  
Julian Deuerling ◽  
Shaun Keck ◽  
Inasya Moelyadi ◽  
Jens-Uwe Repke ◽  
Matthias Rädle

This work presents a novel method for the non-invasive, in-line monitoring of mixing processes in microchannels using the Raman photometric technique. The measuring set-up distinguishes itself from other works in this field by utilizing recent state-of-the-art customized photon multiplier (CPM) detectors, bypassing the use of a spectrometer. This addresses the limiting factor of integration times by achieving measuring rates of 10 ms. The method was validated using the ternary system of toluene–water–acetone. The optical measuring system consists of two functional units: the coaxial Raman probe optimized for excitation at a laser wavelength of 532 nm and the photometric detector centered around the CPMs. The spot size of the focused laser is a defining factor of the spatial resolution of the set-up. The depth of focus is measured at approx. 85 µm with a spot size of approx. 45 µm, while still maintaining a relatively high numerical aperture of 0.42, the latter of which is also critical for coaxial detection of inelastically scattered photons. The working distance in this set-up is 20 mm. The microchannel is a T-junction mixer with a square cross section of 500 by 500 µm, a hydraulic diameter of 500 µm and 70 mm channel length. The extraction of acetone from toluene into water is tracked at an initial concentration of 25% as a function of flow rate and accordingly residence time. The investigated flow rates ranged from 0.1 mL/min to 0.006 mL/min. The residence times from the T-junction to the measuring point varies from 1.5 to 25 s. At 0.006 mL/min a constant acetone concentration of approx. 12.6% was measured, indicating that the mixing process reached the equilibrium of the system at approx. 12.5%. For prototype benchmarking, comparative measurements were carried out with a commercially available Raman spectrometer (RXN1, Kaiser Optical Systems, Ann Arbor, MI, USA). Count rates of the spectrophotometer surpassed those of the spectrometer by at least one order of magnitude at identical target concentrations and optical power output. The experimental data demonstrate the suitability and potential of the new measuring system to detect locally and time-resolved concentration profiles in moving fluids while avoiding external influence.


2011 ◽  
Vol 211-212 ◽  
pp. 465-468
Author(s):  
De Wei Chen

Since the development almost a decade ago of the first biosensor based on surface plasmon resonance (SPR), the use of this technique has increased steadily. In this study, we theoretically investigated the sensing character of SPR sensor with reflection type metallic with Rigorous Coupled Wave Analysis (RCWA) method, and the mechanism is analyzed by the field distribution. It is found that the sensitivity of negative diffraction order, which goes higher quickly as the resonant angle increases, is much greater than that of positive diffraction order.


1987 ◽  
Vol 116 (1_Suppl) ◽  
pp. S312-S317 ◽  
Author(s):  
G. Benker ◽  
D. Reinwein ◽  
H. Creutzig ◽  
H. Hirche ◽  
W. D. Alexander ◽  
...  

Abstract. In spite of the long-established use of antithyroid drugs, there are many unsettled questions connected with this treatment of Graves' disease. There is a lack of controlled prospective trials studying the results of antithyroid drug therapy while considering the many variables such as disease heterogeneity, regional differences, drug dosage and duration of treatment. Therefore, a multicenter study has been set up in order to compare the effects of two fixed doses of methimazole (10 vs 40 mg) with thyroid hormone supplementation on the clinical, biochemical and immunological course of Graves' disease and on remission rates. Experience accumulated so far suggests that treatment is safe using either 10 or 40 mg of methimazole. While there is a tendency for an advantage of the higher dose within the first weeks (higher effectiveness in controlling hyperthyroidism), this difference is not significant. The impact of dosage on remission rates remains to be shown.


Nanophotonics ◽  
2015 ◽  
Vol 4 (4) ◽  
pp. 503-510 ◽  
Author(s):  
Jacek Gosciniak ◽  
Marcus Mooney ◽  
Mark Gubbins ◽  
Brian Corbett

AbstractTwo main ingredients of plasmonics are surface plasmon polaritons (SPP) and localized surface plasmon resonances (LSPR) as they provide a high degree of concentration of electromagnetic fields in the vicinity of metal surfaces, which is well beyond that allowed by the diffraction limit of optics. Those properties have been used in the new technique of heat assisted magnetic recording (HAMR) to overcome an existing limit of conventional magnetic recording by utilizing a near-field transducer (NFT). The NFT designs are based on excitation of surface plasmons on a metal structure, which re-radiate with a subdiffraction limited light spot confined in the near field. In this paper, we propose a novel “droplet”-shaped NFT, which takes full advantage of a recenltly proposed Mach–Zehnder Interferometer (MZI), a coupling arrangement that allows optimal coupling of light to the transducer. The droplet design ensures better impedance match with the recording media and, consequently, better coupling of power. The droplet design results in very high enhancement of the electric field and allows the confinement of light in a spot size much smaller than the present stateof- the-art lollipop transducer.


2015 ◽  
Author(s):  
Pieraugusto Panzalis ◽  
Andrea Deiana ◽  
Sarah Caronni ◽  
Augusto Navone

Marine Protected Areas (MPAs) are acknowledged globally as effective tools for the protection and management of the marine environment; however, to get effective results it is necessary to set up a proper and continuous mapping of the marine territory, in order to gain detailed knowledge of its different aspects. Therefore, the implementation and maintenance of a modern GIS (Geographic Information System) has become an indispensable task for the MPA of Tavolara - Punta Coda Cavallo to collect, aggregate, classify, and track the conducted mapping activities. Between 2011 and 2012 the sea bottom of the MPA was surveyed using different methods: by means of a multi-beam echo sounder and of a side scan sonar, as well as conducting fast scientific scuba divings with re-breathers and underwater position system technologies. High resolution geodatasets, characterized by a significantly high quality in representing and describing the sea bottom and its habitats, were produced in both feature (scale up to 1:1.250) and raster formats (up to 30cm/pixel for sonar images and 1m/pixel for bathymetry) and they currently constitute the basis of the MPA's GIS, including its 3D applications and its web map services for desktop and mobile devices (iPhone & Android). To update the above described geodatasets during time, acquiring new data on the conservation targets considered in monitoring activities, among which the status of P. oceanica meadows is of the most important ones, a long term mapping plan was realized on the basis of an innovative methodology elaborated by the MPA considering both the wideness of the area and the limited funds available at present. The whole MPA was divided in territorial units by means of a regular grid of square cells having a 100m side with the logic of starting the mapping activities from the mainly important areas and then to spread the surveys up to fill the whole mosaic. All the new data acquired with this methodology could then be mixed, compared and indexed within the same cell and/or in the many already available geodatases, starting from those dated 2006 having a regular grid with square cells of 500m per side.


1970 ◽  
pp. 55
Author(s):  
Inge Andriansen

Dybbøl is the brow of a hill located about 30 km north-east of the border between Denmark and Germany. This area was once the former Danish Duchy of Schleswig, which was under German rule in the period from 1864 to 1920. Dybbøl was also the site of intense fighting during the Schleswig-Holstein Revolt of 1848–50 and the Danish-German War of 1864. There are remains of both Danish and German fortifications and earthworks, along with large mass graves in which troops from Denmark, Schleswig-Holstein and Germany lie buried. After a plebiscite about the placing of the border was held in 1920, Schleswig was divided up, and the northern part – which included Dybbøl – became part of Denmark. This was followed by a comprehensive ”Danishification” of the cultural landscape, which had previously been dominated by a large Prussian victory monument and numerous German memorial stones. A Danish national park was set up at Dybbøl in 1924, with the backing of the local population and financial sup- port from a national collection appeal, and formally opened by the Danish prime minister. After this, Dybbøl became the epitome of the institutionalised cultural heritage of the state of Denmark, and would almost certainly be included in any ”cultural canon” of the most significant geographical locations that have helped shape the Danish sense of national identity. However, Dybbøl also features another – less comfortable – aspect of the Danish cultural heritage, bearing witness to Danish acts of vandalism perpetrated against the German monuments found here. Any study of the use of the history associated with Dybbøl uncovers layer upon layer of episodes that speak of conflicting interests and countless metamorphoses that led to the site being imbued with new values and a sequence of new identities. And in step with the resurgence of nationalist sentiments in Denmark since the mid-1980s, there has been a corresponding, strengthened re-annexation of the cultural heritage associated with Dybbøl. The need to cling on to and retain establis- hed, familiar positions and a fundamental sense of belonging are well-known aspects of the process of globalisation, and are seen throughout the world. In Dybbøl, this deep-felt need has resulted in the construction of a Danish fortification, and the Danish flag flying atop the many flagpoles has become more frequent sight. This process can also be interpreted as an expression of Danish foreign policy taking on a more active role in the world.


1952 ◽  
Vol 17 (2) ◽  
pp. 105-116 ◽  
Author(s):  
Hao Wang

Certain axiomatic systems involve more than one category of fundamental objects; for example, points, lines, and planes in geometry; individuals, classes of individuals, etc. in the theory of types or in predicate calculi of orders higher than one. It is natural to use variables of different kinds with their ranges respectively restricted to different categories of objects, and to assume as substructure the usual quantification theory (the restricted predicate calculus) for each of the various kinds of variables together with the usual theory of truth functions for the formulas of the system. An axiomatic theory set up in this manner will be called many-sorted. We shall refer to the theory of truth functions and quantifiers in it as its (many-sorted) elementary logic, and call the primitive symbols and axioms (including axiom schemata) the proper primitive symbols and proper axioms of the system. Our purpose in this paper is to investigate the many-sorted systems and their elementary logics.Among the proper primitive symbols of a many-sorted system Tn (n = 2, …, ω) there may be included symbols of some or all of the following kinds: (1) predicates denoting the properties and relations treated in the system; (2) functors denoting the functions treated in the system; (3) constant names for certain objects of the system. We may either take as primitive or define a predicate denoting the identity relation in Tn.


Author(s):  
Etsuko Takushi Crissey

In September, 1945, with most Okinawans still in refugee camps, the U.S. military ordered elections for civilian leaders in which women were granted the right to vote for the first time, seven months earlier than in mainland Japan. Yet they were far more concerned about the many rapes committed by American soldiers. Women and girls were abducted from fields while searching for food, dragged away from their homes, and assaulted in front of their families. After months of inaction, the U.S. military decided to set up “special amusement areas” for prostitution in certain towns. Some Okinawans favoured this policy as a “breakwater” to protect women and children of “good” families, while others opposed it as exploitation of women. In 1967, at the peak of the Vietnam War, an estimated 10,000 women engaged in prostitution. In 1948 the U.S. military rescinded a ban on marriages between U.S. soldiers and Okinawan women that failed to prevent couples from having intimate relations and living together. Still, commanding officers pressured soldiers not to marry, threatening disciplinary transfers. By 1967, among thousands of biracial children in Okinawa, about half were raised by mothers or their relatives with little or no financial support from fathers.


2013 ◽  
pp. 399-424 ◽  
Author(s):  
Graham Heaslip

The term civil military coordination (CIMIC) suggests the seamless division of labor between aid workers and international military forces. The images of humanitarian organizations distributing food and medicines under the protection of military forces, or aid workers and military working together to construct refugee camps, set up field hospitals, provide emergency water and sanitation, et cetera, has become more frequent. The media coverage from crises such as New Orleans, Kosovo, the tsunami in Asia, Pakistan, Liberia, Sierra Leone, Chad, and more recently Haiti and Japan, has heightened the expectation of a smooth interaction between humanitarian organizations and military forces. Due to fundamental differences between international military forces, humanitarian and development organizations (in terms of the principles and doctrines guiding their work, their agendas, operating styles, and roles), the area of civil military coordination in disaster relief has proven to be more difficult than other interagency relationships. This chapter will identify the many factors that render integration and collaboration problematic between diverse organizations, and especially so between civilian and military agencies. The chapter will conclude with proposals to improve CIMIC within disaster relief.


2020 ◽  
pp. 11-30
Author(s):  
Jack Parkin

Chapter 1 opens the lid on Bitcoin so that all of its attributes, problems, and connotations come spilling out. At the same time, it pulls these disparate strands back into focus by outlining the many discrepancies examined in subsequent chapters. So while in some ways the chapter acts like a primer for cryptocurrencies, blockchains, and their political economies, the material laid out works to set up the book’s underlying argument: asymmetric concentrations of power inevitably form though processes of algorithmic decentralisation. In the process, a short history of Bitcoin introduces some of its key stakeholders as well as some of its core technical functions.


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