Examinando por Autor "Granados, D."

Mostrando 1 - 2 de 2

Restringido
Analysis and Performance of Lumped-Element Kinetic Inductance Detectors for W-Band
(Institute of Electrical and Electronics Engineers, 2021-01-03) Aja, B.; De Ory, M. C.; De la Fuente, L.; Artal, E.; Pascual, J. P.; Teresa Magaz, M.; Granados, D.; Gómez, A.; Agencia Estatal de Investigación (AEI); Comunidad de Madrid; Aja, B. [0000-0002-4229-2334]; De la Fuente, L. [0000-0003-1403-1660]; Artal, E. [0000-0002-2569-1894]; Pascual, J. P. [0000-0003-2123-0502]; Granados, D. [0000-0001-7708-9080]; Gómez, A. [0000-0002-8752-1401]; Centros de Excelencia Severo Ochoa, INSTITUTO MADRILEÑO DE ESTUDIOS AVANZADOS EN NANOCIENCIA, SEV-2016-0686
Lumped-element superconducting resonators are a promising technology for their use in millimeter-wave observations and quantum computing applications that require large arrays of extremely sensitive detectors. Among them, lumped-element kinetic inductance detectors (LEKIDs) have shown good performance in the submillimeter band in several earth-based telescopes. In this work, LEKIDs for their use as millimeter-wave receivers of astronomical applications are presented. LEKID arrays using a thin bilayer of superconducting titanium/aluminum (Ti/Al), deposited on the silicon substrate, have been designed and fabricated. The design of a dual-polarization LEKID with the goal of detection at the W-band for two orthogonal polarizations is described and a fabricated array has demonstrated absorption at ambient temperature. Also, an approximate design methodology of the coupling parameter for LEKIDs' readout, essential for dynamic range optimization of the detector under millimeter-wave radiation, is proposed. In addition, the resonance characteristics and coupling factor of the fabricated superconducting resonators using high-quality internal factor Q i under cryogenic temperatures have been analyzed. The design guidelines in this work are applicable to other LEKID arrays, and the presented superconducting Ti/Al thin-film LEKIDs can be used in future receiver arrays in the millimeter bands.
Restringido
Antiphase resonance at X-ray irradiated microregions in amorphous Fe80B20 stripes
(Elsevier BV, 2021-02-15) Urdiroz, U.; Gómez, A.; Magaz, M.; Granados, D.; Sánchez Agudo, M.; Rubio Zuazo, J.; Castro, G. R.; Stan, C.; Tamura, N.; Padmore, H. A.; Müller, C.; McCord, J.; Cebollada, F.; Palomares, F. J.; González, J. M.; Agencia Estatal de Investigación (AEI); 0000-0001-7944-340X; 0000-0002-4768-2219; 0000-0003-0237-6450; 0000-0002-1727-1654
We report on the induction, through X-ray irradiation, of local anisotropy modifications in amorphous Fe80B20 stripes prepared by laser lithography from 15 nm thick films deposited by pulsed laser ablation. Those anisotropy modifications, taking place in a zone having a dimension of 15 μm around the X-ray beam (2 µm width) incidence area center point, lead to an effective transverse-to-the-stripe long axis local magnetic easy axis that can be exploited to stably localize a 180° domain wall, in remanence after saturation with a transverse-to the stripe easy axis dc field. Upon stabilizing that wall it is possible to excite spatially inhomogeneous ferromagnetic resonances nearby the irradiated region (IR). The time dependencies of the magnetization precession at both sides of the IR exhibit a uniform phase shift of 180° over distances of the order of 20 μm from the stabilized domain wall.