Exciting surface plasmons with transformation media

The final publication is available at Springer via http://dx.doi.org/10.1007/s11468-012-9361-5We present a way of exciting surface plasmon polaritons along non-patterned metallic surfaces by means of a flat squeezing slab designed with transformation optics. The slab changes the dispersion relation of incident light, enabling evanescent coupling to propagating surface plasmons. Unlike prism couplers, the proposed device does not introduce reflections at its input interface. Moreover, its compact geometry is suitable for integration. A feasible dielectric implementation of the coupler is suggested. Finally, we show that the angular response of the device can be engineered by using a non-uniform compression factor. As an example, we design a coupler with a half-power angular bandwidth 2. 5 times higher than that of a conventional dielectric coupler. © 2012 Springer Science+Business Media, LLC.Financial support by Spanish Ministerio de Ciencia e Innovacion (contracts CSD2008-00066 and TEC2008-06871-C02, and FPU grant) is gratefully acknowledged.García Meca, C.; Ortuño Molinero, R.; Martí Sendra, J.; Martínez Abietar, AJ. (2012). Exciting surface plasmons with transformation media. Plasmonics. 7(4):701-707. https://doi.org/10.1007/s11468-012-9361-5S70170774Raether H (1988) Surface plasmons on smooth and rough surfaces and on gratings. Springer-Verlag, BerlinBarnes WL, Dereux A, Ebbesen TW (2003) Surface plasmon subwavelength optics. Nature 424:824–830Maier SA (2007) Plasmonics: fundamentals and applications. Springer, New YorkSchuller JA, Barnard ES, Cai W, Jun YC, White JS, Brongersma ML (2010) Plasmonics for extreme light concentration and manipulation. Nat Mater 9:193–204Brongersma ML, Shalaev VM (2010) The case for plasmonics. Science 328:440–441Liu Y, Zentgraf T, Bartal G, Zhang X (2010) Transformational plasmon optics. Nano Lett 10:1991–1997Huidobro PA, Nesterov ML, Martín-Moreno L, García-Vidal FJ (2010) Transformation optics for plasmonics. Nano Lett 10:1985–1990Kadic M, Guenneau S, Enoch S (2010) Transformational plasmonics: cloak, concentrator and rotator for SPPs. Opt Express 18:12027–12032Zhang J, Xiao S, Wubs M, Mortensen NA (2011) Surface plasmon wave adapter designed with transformation optics. ACS Nano 5:4359–4364Pendry JB, Schurig D, Smith DR (2006) Controlling electromagnetic fields. Science 312:1780–1782Leonhardt U (2006) Optical conformal mapping. Science 312:1777–1780Leonhardt U, Philbin TG (2006) General relativity in electrical engineering. New J Phys 8:247Sambles JR, Bradbery GW, Yang F (1991) Optical excitation of surface plasmons: an introduction. Contemp Phys 32:173–183Rahm M, Roberts DA, Pendry JB, Smith DR (2008) Transformation-optical design of adaptive beam bends and beam expanders. Opt Express 16:11555–11567Vasic B, Isic G, Gajic R, Hingerl K (2009) Coordinate transformation based design of confined metamaterial structures. Phys Rev B 79:85103Tichit P, Burokur SN, Lustrac A (2009) Waveguide taper engineering using coordinate transformation technology. Opt Express 18:767–772Zang X, Jiang C (2010) Manipulating the field distribution via optical transformation. Opt Express 18:10168–10176García-Meca C, Tung MM, Galán JV, Ortuño R, Rodríguez-Fortuño FJ, Martí J, Martínez A (2011) Squeezing and expanding light without reflections via transformation optics. Opt Express 19:3562–3575Li J, Han S, Zhang S, Bartal G, Zhang X (2009) Designing the Fourier space with transformation optics. Opt Lett 34:3128–3130Li J, Pendry JB (2008) Hiding under the carpet: a new strategy for cloaking. Phys Rev Lett 101:20390

Long-range and rapid transport of individual nano-objects by a hybrid electrothermoplasmonic nanotweezer

Plasmon-enhanced optical trapping is being actively studied to provide efficient manipulation of nanometre-sized objects. However, a long-standing issue with previously proposed solutions is how to controllably load the trap on-demand without relying on Brownian diffusion. Here, we show that the photo-induced heating of a nanoantenna in conjunction with an applied a.c. electric field can initiate rapid microscale fluid motion and particle transport with a velocity exceeding 10 μm s -1 , which is over two orders of magnitude faster than previously predicted. Our electrothermoplasmonic device enables on-demand long-range and rapid delivery of single nano-objects to specific plasmonic nanoantennas, where they can be trapped and even locked in place. We also present a physical model that elucidates the role of both heat-induced fluidic motion and plasmonic field enhancement in the plasmon-assisted optical trapping process. Finally, by applying a d.c. field or low-frequency a.c. field (below 10 Hz) while the particle is held in the trap by the gradient force, the trapped nano-objects can be immobilized into plasmonic hotspots, thereby providing the potential for effective low-power nanomanufacturing on-chip

Effects of alirocumab on types of myocardial infarction: insights from the ODYSSEY OUTCOMES trial

Aims  The third Universal Definition of Myocardial Infarction (MI) Task Force classified MIs into five types: Type 1, spontaneous; Type 2, related to oxygen supply/demand imbalance; Type 3, fatal without ascertainment of cardiac biomarkers; Type 4, related to percutaneous coronary intervention; and Type 5, related to coronary artery bypass surgery. Low-density lipoprotein cholesterol (LDL-C) reduction with statins and proprotein convertase subtilisin–kexin Type 9 (PCSK9) inhibitors reduces risk of MI, but less is known about effects on types of MI. ODYSSEY OUTCOMES compared the PCSK9 inhibitor alirocumab with placebo in 18 924 patients with recent acute coronary syndrome (ACS) and elevated LDL-C (≥1.8 mmol/L) despite intensive statin therapy. In a pre-specified analysis, we assessed the effects of alirocumab on types of MI. Methods and results  Median follow-up was 2.8 years. Myocardial infarction types were prospectively adjudicated and classified. Of 1860 total MIs, 1223 (65.8%) were adjudicated as Type 1, 386 (20.8%) as Type 2, and 244 (13.1%) as Type 4. Few events were Type 3 (n = 2) or Type 5 (n = 5). Alirocumab reduced first MIs [hazard ratio (HR) 0.85, 95% confidence interval (CI) 0.77–0.95; P = 0.003], with reductions in both Type 1 (HR 0.87, 95% CI 0.77–0.99; P = 0.032) and Type 2 (0.77, 0.61–0.97; P = 0.025), but not Type 4 MI. Conclusion  After ACS, alirocumab added to intensive statin therapy favourably impacted on Type 1 and 2 MIs. The data indicate for the first time that a lipid-lowering therapy can attenuate the risk of Type 2 MI. Low-density lipoprotein cholesterol reduction below levels achievable with statins is an effective preventive strategy for both MI types.For complete list of authors see http://dx.doi.org/10.1093/eurheartj/ehz299</p

The proximate composition of three marine pelagic fish: blue whiting (Micromesistius poutassou), boarfish (Capros aper) and Atlantic herring (Clupea harengus)

peer reviewedThis study presents data from an in-depth proximate compositional analysis of three marine fish species: blue whiting (Micromesistius poutassou), boarfish (Capros aper) and Atlantic herring (Clupea harengus). These fish contained significant amounts of protein (16–17%), lipids (4–11%) and minerals (2–6% ash). The proteins, particularly from boarfish, had close to optimum amino acid profiles for human and fish nutrition. They compared favourably with other fish species in terms of total lipids and relative concentration of the omega-3 fatty acids docosahexaenoic acid and eicosapentaenoic acid (11.8–13.3% and 5.9–8.1% in triacylglycerols [TG] and 24.6–35.4% and 5.8–12.0% in phospholipids [PL]). Atlantic herring had the highest lipid content among the three fish and was found to contain high levels of PL poly-unsaturated fatty acids, including omega-3 fatty acids. Minerals detected in the fish included calcium (272–1,520 mg/100 g), phosphorus (363–789 mg/100 g), iron (1.07–2.83 mg/100 g), magnesium (40.70–62.10 mg/100 g), potassium (112.00–267.00 mg/100 g), selenium (0.04–0.06 mg/100 g), sodium (218.00–282.00 mg/100 g) and zinc (1.29–5.57 mg/100 g). Boarfish had the highest ash fraction and also the highest levels of all the minerals, except potassium. Atlantic herring had considerably lower mineral content compared with the other two species and, levels detected were also lower than those reported in previously published studies. Heavy metals contents were quantified, and levels were significantly below the maximum allowable limits for all elements except arsenic, which ranged from 1.34 to 2.44 mg/kg in the three fish species. Data outlined here will be useful for guiding product development. Future studies would benefit from considering catch season, sex and developmental stage of the fish

Effect of alirocumab on mortality after acute coronary syndromes. An analysis of the ODYSSEY OUTCOMES randomized clinical trial

Background: Previous trials of PCSK9 (proprotein convertase subtilisin-kexin type 9) inhibitors demonstrated reductions in major adverse cardiovascular events, but not death. We assessed the effects of alirocumab on death after index acute coronary syndrome. Methods: ODYSSEY OUTCOMES (Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab) was a double-blind, randomized comparison of alirocumab or placebo in 18 924 patients who had an ACS 1 to 12 months previously and elevated atherogenic lipoproteins despite intensive statin therapy. Alirocumab dose was blindly titrated to target achieved low-density lipoprotein cholesterol (LDL-C) between 25 and 50 mg/dL. We examined the effects of treatment on all-cause death and its components, cardiovascular and noncardiovascular death, with log-rank testing. Joint semiparametric models tested associations between nonfatal cardiovascular events and cardiovascular or noncardiovascular death. Results: Median follow-up was 2.8 years. Death occurred in 334 (3.5%) and 392 (4.1%) patients, respectively, in the alirocumab and placebo groups (hazard ratio [HR], 0.85; 95% CI, 0.73 to 0.98; P=0.03, nominal P value). This resulted from nonsignificantly fewer cardiovascular (240 [2.5%] vs 271 [2.9%]; HR, 0.88; 95% CI, 0.74 to 1.05; P=0.15) and noncardiovascular (94 [1.0%] vs 121 [1.3%]; HR, 0.77; 95% CI, 0.59 to 1.01; P=0.06) deaths with alirocumab. In a prespecified analysis of 8242 patients eligible for ≥3 years follow-up, alirocumab reduced death (HR, 0.78; 95% CI, 0.65 to 0.94; P=0.01). Patients with nonfatal cardiovascular events were at increased risk for cardiovascular and noncardiovascular deaths (P<0.0001 for the associations). Alirocumab reduced total nonfatal cardiovascular events (P<0.001) and thereby may have attenuated the number of cardiovascular and noncardiovascular deaths. A post hoc analysis found that, compared to patients with lower LDL-C, patients with baseline LDL-C ≥100 mg/dL (2.59 mmol/L) had a greater absolute risk of death and a larger mortality benefit from alirocumab (HR, 0.71; 95% CI, 0.56 to 0.90; Pinteraction=0.007). In the alirocumab group, all-cause death declined wit h achieved LDL-C at 4 months of treatment, to a level of approximately 30 mg/dL (adjusted P=0.017 for linear trend). Conclusions: Alirocumab added to intensive statin therapy has the potential to reduce death after acute coronary syndrome, particularly if treatment is maintained for ≥3 years, if baseline LDL-C is ≥100 mg/dL, or if achieved LDL-C is low. Clinical Trial Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01663402

Raman spectroscopy, assisted by X-ray fluorescence and laser-induced breakdown spectroscopy, to characterise original and altered mineral phases in the NWA 2975 Martian shergottite

A fragment of the NWA 2975 Martian meteorite, an enriched basaltic shergottite, was analysed to complete its geochemical characterisation performed 10 years ago. By this means, the feasibility of the employed techniques in a combined way for present and future space exploration missions can be tested. For this aim, Raman spectroscopy was used supported by micro energy dispersive X-ray fluorescence (mu-EDXRF) and laser-induced breakdown spectroscopy (LIBS) for an accurate interpretation of molecular and elemental results. Raman spectroscopy results from two setups, InVia from Renishaw and RLS Simulator, were compared. The major minerals detected by Raman spectroscopy were pyroxenes (mainly augite, pigeonite and enstatite) and plagioclases (mainly shocked maskelynite). Raman spectroscopy allowed defining different metal compositions for these main minerals based on the secondary Raman spectroscopy bands in the 200-500 cm(-1) region. In addition, other minerals were found such as merrillite, as well as pyrrhotite and apatite, in several veins and cracks of the meteorite, in agreement with the initial report by the Meteoritical Bulletin. Moreover, it should be highlighted that coesite was found for the very first time in this meteorite