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Frank Bello

Publications and source records attributed to Frank Bello.

4 recordsLinked to original sources

Optical and thermal analysis of the light-heat conversion process employing an antenna-based hybrid plasmonic waveguide for HAMR

We investigate a tapered, hybrid plasmonic waveguide which has previously been proposed as an optically efficient near-field transducer (NFT), or component thereof, in several devices which aim to exploit nanofocused light. We numerically analyze how light is transported through the waveguide and ultimately focused via effective-mode coupling and taper optimization. Crucial dimensional parameters in this optimization process are identified that are not only necessary to achieve maximum optical throughput, but also optimum thermal performance with specific application towards heat-assisted magnetic recording (HAMR). It is shown that existing devices constructed on similar waveguides may benefit from a heat spreader to avoid deformation of the plasmonic element which we achieve with no cost to the optical efficiency. For HAMR, our design is able to surpass many industry requirements in regard to both optical and thermal efficiency using pertinent figure of merits like 8.5% optical efficiency.

physics.optics

CMOS compatible multi-band plasmonic TE-pass polarizer

A CMOS-compatible plasmonic TE-pass polarizer capable of working in the O, E, S, C, L, and U bands is numerically analyzed. The device is based on an integrated hybrid plasmonic waveguide (HPW) with a segmented metal design. The segmented metal will avoid the propagation of the TM mode, confined in the slot of the HPW, while the TE fundamental mode will pass. The TE mode is not affected by the metal segmentation since it is confined in the core of the HPW. The concept of the segmented metal can be exploited in a plasmonic circuit with HPWs as the connecting waveguides between parts of the circuit and in a silicon photonics circuit with strip or slab waveguides connecting the different parts of the circuit. Using 3D FDTD simulations, it is shown that for a length of 5.5 {\mu}m the polarization extinction ratios are better than 20 dB and the insertion losses are less than 1.7 dB over all the optical communication bands.

physics.optics

Near-field plasmonics for generation of phonon lasing in a thermal nanomachine

Recent advances in near-field plasmonic metamaterials, such as nanoresonators or transducers, have demonstrated the ability to generate localized fields of high intensity, and thus maintain relatively large nanoscale heat gradients on the order of $10^1-10^2$~K/nm. A plasmonic near-field transducer (NFT) can achieve such large gradients, making population inversion achievable within phononic media. We herein develop a thermal nanomachine composed of a nanoscale phononic laser using InGaAs quantum dot media where an NFT serves as the plasmonic energy source. We show, on demand, the generation of phonons while having full control of the phonon lasing medium. We also demonstrate the ability to obtain population inversion of a photonic transition in the system if one chooses.

cond-mat.mes-hall

Alpha Decay of Superheavy Nuclei

Recently synthesis of superheavy nuclei has been achieved in hot fusion reactions. A systematic theoretical calculation of alpha decay half-lives in this region of the periodic system, may be useful in the identification of new nuclei in these type of reactions. Alpha decay half-lives are obtained in the framework of the barrier penetration theory, built with the use of proximity and Coulomb forces. It is estimated from a classical viewpoint, a possible angular momentum maximum value for odd and odd-odd nuclei alpha particles. The masses of the nuclei are obtained from a macro-microscopic model, with the use of the two center shell model. Decay half-lives are compared with experimental results.

nucl-th