Effective electric and magnetic properties of metasurfaces in transition from crystalline to amorphous state

In this paper we theoretically study electromagnetic reflection, transmission, and scattering properties of periodic and random arrays of particles which exhibit both electric-mode and magnetic-mode resonances. We compare the properties of regular and random grids and explain recently observed dramatic differences in resonance broadening in the electric and magnetic modes of random arrays. We show that randomness in the particle positioning influences equally on the scattering loss from both electric and magnetic dipoles, however, the observed resonance broadening can be very different depending on the absorption level in different modes as well as on the average electrical distance between the particles. The theory is illustrated by an example of a planar metasurface composed of cut-wire pairs. We show that in this particular case at the magnetic resonance the array response is almost not affected by positioning randomness due to lower frequency and higher absorption losses in that mode. The developed model allows predictions of behavior of random grids based on the knowledge of polarizabilities of single inclusions.Comment: 13 pages, 5 figures, and submitted to PR

Symmetry and reciprocity constraints on diffraction by gratings of quasi-planar particles

Symmetry and reciprocity constraints on polarization state of the field diffracted by gratings of quasi-planar particles are considered. It is shown that the optical activity effects observed recently in arrays of quasi-planar plasmonic particles on a dielectric substrate are due to the reflection of the field at the air-dielectric slab interface and are proportional to this reflection coefficient.Comment: 11 pages, 3 figures, 12 references; minor corrections for better appearanc

Full light absorption in single arrays of spherical nanoparticles

In this paper we show that arrays of core-shell nanoparticles function as effective thin absorbers of light. In contrast to known metamaterial absorbers, the introduced absorbers are formed by single planar arrays of spherical inclusions and enable full absorption of light incident on either or both sides of the array. We demonstrate possibilities for realizing different kinds of symmetric absorbers, including resonant, ultra-broadband, angularly selective, and all-angle absorbers. The physical principle behind these designs is explained considering balanced electric and magnetic responses of unit cells. Photovoltaic devices and thermal emitters are the two most important potential applications of the proposed designs.Comment: (e.g.: 18 pages, 5 figures

Analisis Kapasitas Ruang Udara Medan East TMA Setelah Implementasi Rute PBN (RNAV1)

Ruang udara terdiri atas beberapa sektor dengan keterbatasan atau kapasitas yang tentunya berbeda-beda. Hal ini dapat dipengaruhi banyak faktor yang kemudian dapat mempengaruhi optimalisasi ruang udara tersebut. Kapasitas sistem ATC dengan beban kerja sebagai indikator yang diperhituangkan, menjadi salah satu faktor yang difokuskan dalam menganalisis kapasitas ruang udara pada penelitian ini. Metode yang digunakan dalam penelitian ini adalah Pessimistic Sector Capacity. Metode ini mengadopsi Document Eurocontrol Experiment Center (EEC) Note no.21/23 yang merupakan pengembangan metode regresi ATC Capacity Analyser Tool (CAPAN) untuk menghitung kapasitas sebuah sektor serta menganalisis regresi beban kerja petugas ATC dibandingkan dengan jumlah penerbangan pada suatu sektor. Data primer pada penelitian ini diperoleh melalui survei langsung terhadap kegiatan ATC yaitu saat memberikan pelayanan lalu lintas penerbangan pada suatu sektor ruang udara selama 1 jam pada saat peak hours dalam kurun waktu 30 hari. Data sekunder yang diperlukan untuk mendukung analisis yaitu terkait jumlah penerbangan saat jam puncak, kondisi cuaca, dan rencana penerbangan. Hasil penelitian menunjukkan, setelah diimplementasikannya PBN (RNAV1), terdapat peningkatan nilai kapasitas ruang udara di sektor Medan East TMA dari 22 traffic/jam menjadi 25 traffic/jam. Selanjutnya, analisis ini dapat dijadikan baseline guna peningkatan kapasitas ruang udara di masa yang akan datang dalam rangka antisipasi permintaan lalu lintas penerbangan yang terus meningkat