Material- and shape-dependent optical modes of hyperbolic spheroidal nano-resonators.

Hyperbolic nanoresonators, composed of anisotropic materials with opposite signs of permittivity, have unique optical properties due to a large degree of freedom that hyperbolic dispersion provides in designing their response. Here, we focus on uniaxial hyperbolic nanoresonators composed of a model silver-silica multilayer in the form of spheroids with a broad aspect ratio encompassing both prolate and oblate particles. The origin and evolution of the optical response and mode coupling are investigated using both numerical (T-matrix and FDTD) and theoretical methods. We show the tunability of the optical resonances and the interplay of the shape and material anisotropy in determining the spectral response. Depending on the illumination conditions as well as shape and material anisotropy, a single hyperbolic spheroid can show a dominant electric resonance, behaving as a pure metallic nanoparticle, or a strong dipolar magnetic resonance even in the quasistatic regime. The quasistatic magnetic response of indicates a material-dependent origin of the mode, which is obtained due to coupling of the magnetic and electric multipoles. Such coupling characteristics can be employed in various modern applications based on metasurfaces.

Hall effect sensors using polarized electron cloud spin orientation control.

A silicon microring circuit embedded gold film with unique characteristics is proposed for Hall effect, current, and temperature sensing applications. The microring circuit is operated by the input polarized laser sources, in which the space-time distortion control can be employed. A gold film is embedded at the microring center. The whispering gallery mode (WGM) is generated and applied for plasmonic waves, from which the trapped electron cloud oscillation is formed. Through the input port, the input polarized light of 1.55 µm wavelength fed into the space-time control circuit. Spin-up |↑〉(|0〉) and spin-down |↓〉(|1〉) of polarized electrons result when the gold film is illuminated by the WGM. The electric current passing through the gold film generates a magnetic field (B), which is orthogonal to the electric field. Hall voltage is obtained at the output of the circuit, from which the microring space-time circuit can operate for Hall's effect, current, and temperature sensing device. The simulation results obtained have shown that when the input power of 100-500 mW is applied, the optimum Hall effect, current, and temperature sensitivities are 0.12 µVT-1 , 0.9 µVA-1 , and 6.0 × 10-2 µVK-1 , respectively. The Hall effects, current, and temperature sensors have an optimum response time of 1.9 fs.

3D-quantum interferometer using silicon microring-embedded gold grating circuit.

A 3D (three-dimensional) quantum interferometer consisting of a silicon microring circuit proposed. The interferometer based on the electron spin cloud projections generated by microring-embedded gold grating. The electron cloud oscillations result from the excitation of the gold grating at the center of the silicon microring by the dark soliton pulse of 1.50 µm center wavelength. The electron cloud spin-down, spin-up automatically formed in the two axes (x, y, respectively) and propagated along the z-axis. In this proposal, the sensing mechanism of the circuit is manipulated by varying the reflector gold lengths of the sensing arm. The electron cloud spin coupled and changed by changing the gold lengths. The sensitivity measurement of the 3D quantum interferometer for three gold layer lengths of 100 nm, 500 nm, and 1,000 nm is (47.62 nm fs-1 , ±0.4762 fs-1 , ±0.01 nm-1 ), (238.10 nm fs-1 , ±0.4762 fs-1 , ±0.002 nm-1 ), (476.20 nm fs-1 , ±0.4762 fs-1 , ±0.001 nm-1 ), respectively. The used circuit parameters are the real ones that can be fabricated by the currently available technology. Moreover, the silicon micro ring circuit acts as a plasmonic antenna, which can apply for wireless quantum communication. The electron cloud spin projection space-time control can apply for quantum cellular automata.