Shorted waveguide ferromagnetic resonance ͑FMR͒ measurements were made at 9.5 GHz for pulsed laser deposited yttrium iron garnet ͑YIG͒, MnZn ferrite, and NiZn ferrite films with thicknesses of 1.8, 0.5, and 1.5 m, respectively. The FMR field versus the field angle confirmed the operational assumption of a uniform mode response. For the YIG, the linewidth was 10 Oe when the external field and magnetization vectors were perpendicular to the disk ͑perpendicular FMR͒ and increased smoothly to a maximum value of 27 Oe when the field and magnetization were in the film plane ͑parallel FMR͒. For the MnZn, the linewidth was 49 Oe at perpendicular FMR, increased with the angle between the film normal and the external field to a broad maximum of 80 Oe at 35°, and then dropped to 65 Oe at parallel FMR. For the NiZn, the linewidth was 310 Oe at perpendicular FMR, increased with the field angle to a broad maximum of 1530 Oe at 45°, and then dropped to 960 Oe at parallel FMR. The linewidths were larger than predicted for reasonable values of the Landau-Lifshitz damping and showed angle dependences which indicated nonintrinsic contributions to the loss. Two magnon scattering was used to model these linewidth differences. The angle dependences of the excess linewidths show qualitative agreement with the two magnon predictions, with inhomogeneity sizes in the submicron range and volume fractions below 1%.

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High power demand, emission regulations, high efficient design are the prime requirement for the design of turbochargers. VGT (variable geometry turbocharging) is most widely used and explored compared to other available options to deal with today’s market. VGT turbochargers offers several potential benefits when compared to fixed geometry turbochargers, like increased transient response, wide operating range, improved torque characteristics, boost pressure recovery and better fuel economy. In this paper performance variation of compressor and turbine viz, — Pressure ratio, mass flow, and efficiency, and throat area are optimized to reach to the operating point of the engine. Different vane angles (0, +4°, +7°, +10° & +15°) are studied to understand the variation of transient turbine response. Authors also discussed the mechanical conceptualization of the VANT (Variable area nozzle) in thought of having great impact on the performance.

Using finite integration technique, the authors investigate the properties of a cross-nanoslot formed in silver film, from the perspective of a plasmonic antenna, and examine the transmission of light through its periodic array. The cross-slot nanoantenna (CSNA) can enhance the intensity of near field by orders of magnitude, independent of polarisation of incident light, and emit omnidirectionally when excited by two identical sources of orthogonal polarisation operating in phase quadrature. An array of CSNA exhibit extraordinary transmission, which can be enhanced further by placing complementary cross-nanostripe array at an optimum position. To the authors' best knowledge, this is the first exploration of a cross-nanoslot as an antenna.1. Introduction: An antenna acts as a progression device that converts guided electromagnetic (EM) waves into free space wave and vice versa. Recently, there has been a growing interest towards miniaturisation of RF antenna designs to optical frequency range for utilisation of their potential in the field of nanophotonics and plasmonics. It is believed that such nanoantennas could play a similar role in optical frequency range as played by conventional antennas in RFs [1-3]. Besides transmission and reception of optical signals these nanostructures may also find several other applications, such as biological imaging, efficient confinement and enhancement of light at nanoscale, efficient light coupling to nanoscale, guiding and redirecting light at nanoscale, near field and far field inter conversion, optical information processing at nanoscale, nanolight emitting devices/sources, nonlinear medium as an optical switch, solar cells, for realisation of metamaterials, etc. [4][5][6][7][8][9]. Thus, plasmonic nanoantennae may have much broader applications as compared with their RF counterparts and this urges for the exploration and design of novel antennas in optical frequencies. In this context, we can borrow ideas from highly developed RF antenna designs [10,11] to produce more sophisticated optical antennas.In this Letter, we investigate the EM properties of a crossnanoslot from the viewpoint of antenna and study optical transmission through its periodic array. The cross-slot nanoantenna (CSNA) is formed by extending the feedgap of the recently proposed slot nanoantenna (SNA) [12], so as to form another slot orthogonal to the former. The structures of SNA and CSNA formed in a silver film on a silica substrate are shown in Figs. 1a and b, respectively. Using CST Microwave Studio (MWS), which is a commercial 3D EM simulator based on finite integration technique [13], first we investigate the spectral response of CSNA and observe that it can enhance intensity of near field by orders of magnitude, independent of polarisation. Secondly, we calculate the far field emission for various angles of polarisation of incident light. It is found that the azimuthal pattern of CSNA maintains the shape but rotates with the polarisation angle. The emission from CSNA is omnidirectional when operated...

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