Now showing items 1-20 of 21

    • All-metallic ε-near-zero (ENZ) lens based on ultra-narrow hollow rectangular waveguides: experimental results 

      Orazbayev, Bakhtiyar Upna Orcid; Torres Landívar, Víctor Upna; Pacheco-Peña, Víctor Upna Orcid; Falcone Lanas, Francisco Javier Upna Orcid; Teniente Vallinas, Jorge Upna Orcid; Beruete Díaz, Miguel Upna Orcid; Sorolla Ayza, Mario Upna; Navarro Cía, Miguel Upna Orcid; Engheta, Nader (IEEE, 2014)   Contribución a congreso / Biltzarrerako ekarpena  OpenAccess
      Here we perform numerical and experimental investigation of plano-concave all-metallic ε-near-zero (ENZ) lens with operational frequency f = 144 GHz. The ENZ lens is achieved by stacking an array of narrow hollow rectangular ...
    • Direct observation of ideal electromagnetic fluids 

      Li, Hao; Zhou, Ziheng; Sun, Wangyu; Lobet, Michaël; Engheta, Nader; Liberal Olleta, Íñigo Upna Orcid; Li, Yue (Springer Nature, 2022)   Artículo / Artikulua  OpenAccess
      Near-zero-index (NZI) media have been theoretically identified as media where electromagnetic radiations behave like ideal electromagnetic fluids. Within NZI media, the electromagnetic power flow obeys equations similar ...
    • Dispersion coding of ENZ media via multiple photonic dopants 

      Zhou, Ziheng; Li, Hao; Sun, Wangyu; He, Yijing; Liberal Olleta, Íñigo Upna Orcid; Engheta, Nader; Feng, Zhenghe; Li, Yue (Springer Nature, 2022)   Artículo / Artikulua  OpenAccess
      Epsilon-near-zero (ENZ) media are opening up exciting opportunities to observe exotic wave phenomena. In this work, we demonstrate that the ENZ medium comprising multiple dielectric photonic dopants would yield a comb-like ...
    • Effect of epsilon-near-zero modes on the casimir interaction between ultrathin films 

      Gong, Tao; Liberal Olleta, Íñigo Upna Orcid; Spreng, Benjamin; Camacho, Miguel; Engheta, Nader; Munday, Jeremy N. (American Physical Society, 2023)   Artículo / Artikulua  OpenAccess
      Vacuum fluctuation-induced interactions between macroscopic metallic objects result in an attractive force between them, a phenomenon known as the Casimir effect. This force is the result of both plasmonic and photonic ...
    • Electrically switchable Casimir forces using transparent conductive oxides 

      Gong, Tao; Spreng, Benjamin; Camacho, Miguel; Liberal Olleta, Íñigo Upna Orcid; Engheta, Nader; Munday, Jeremy N. (American Physical Society, 2022)   Artículo / Artikulua  OpenAccess
      Casimir forces between charge-neutral bodies originate from quantum vacuum fluctuations of electromagnetic fields, which exhibit a critical dependence on material's electromagnetic properties. Over the years, in situ ...
    • Experimental demonstration of deeply subwavelength dielectric sensing with epsilon-near-zero (ENZ) waveguides 

      Beruete Díaz, Miguel Upna Orcid; Engheta, Nader; Pacheco-Peña, Víctor Upna Orcid (American Institute of Physics, 2022)   Artículo / Artikulua  OpenAccess
      In this Letter, an all metallic sensor based on ε-near-zero (ENZ) metamaterials is studied both numerically and experimentally when working at microwave frequencies. To emulate an ENZ medium, a sensor is made by using a ...
    • Experimental realization of an epsilon-near-zero graded-index metalens at terahertz frequencies 

      Pacheco-Peña, Víctor Upna Orcid; Engheta, Nader; Kuznetsov, Sergei A.; Gentselev, Alexandr; Beruete Díaz, Miguel Upna Orcid (American Physical Society, 2017)   Artículo / Artikulua  OpenAccess
      The terahertz band has been historically hindered by the lack of efficient generators and detectors, but a series of recent breakthroughs have helped to effectively close the “terahertz gap.” A rapid development of terahertz ...
    • Geometry-independent antenna based on Epsilon-near-zero medium 

      Li, Hao; Zhou, Ziheng; He, Yijing; Sun, Wangyu; Li, Yue; Liberal Olleta, Íñigo Upna Orcid; Engheta, Nader (Springer Nature, 2022)   Artículo / Artikulua  OpenAccess
      It is well known that electromagnetic radiation from radiating elements (e.g., antennas, apertures, etc.) shows dependence on the element’s geometry shape in terms of operating frequencies. This basic principle is ...
    • Geometry-invariant resonant cavities 

      Liberal Olleta, Íñigo Upna Orcid; Mahmoud, A. M.; Engheta, Nader (Springer Nature, 2016)   Artículo / Artikulua  OpenAccess
      Resonant cavities are one of the basic building blocks in various disciplines of science and technology, with numerous applications ranging from abstract theoretical modelling to everyday life devices. The eigenfrequencies ...
    • Lensing system and Fourier transformation using epsilon-near-zero metamaterials 

      Navarro Cía, Miguel Upna Orcid; Beruete Díaz, Miguel Upna Orcid; Sorolla Ayza, Mario Upna; Engheta, Nader (American Physical Society, 2012)   Artículo / Artikulua  OpenAccess
      Metamaterials and metastructures with effective relative permittivity near zero exhibit unusual wave properties such as uniform phase distributions across such domains. Here we discuss the possibility of using ε-near-zero ...
    • Manipulating thermal emission with spatially static fluctuating fields in arbitrarily shaped epsilon-near-zero bodies 

      Liberal Olleta, Íñigo Upna Orcid; Engheta, Nader (National Academy of Sciences, 2018)   Artículo / Artikulua  OpenAccess
      The control and manipulation of thermal fields is a key scientific andtechnological challenge, usually addressed with nanophotonic struc-tures with a carefully designed geometry. Here, we theoreticallyinvestigate a different ...
    • Mechanical 144GHz beam steering with all-metallic epsilon-near-zero lens antenna 

      Pacheco-Peña, Víctor Upna Orcid; Torres Landívar, Víctor Upna; Orazbayev, Bakhtiyar Upna Orcid; Beruete Díaz, Miguel Upna Orcid; Navarro Cía, Miguel Upna Orcid; Sorolla Ayza, Mario Upna; Engheta, Nader (AIP Publishing, 2014)   Artículo / Artikulua  OpenAccess
      An all-metallic steerable beam antenna composed of an ε-near-zero (ENZ) metamaterial lens is experimentally demonstrated at 144 GHz (λ0 = 2.083 mm). The ENZ lens is realized by an array of narrow hollow rectangular waveguides ...
    • Momentum considerations inside near-zero index materials 

      Lobet, Michaël; Liberal Olleta, Íñigo Upna Orcid; Vertchenko, Larissa; Lavrinenko, Andrei V.; Engheta, Nader; Mazur, Eric (Springer Nature, 2022)   Artículo / Artikulua  OpenAccess
      Near-zero index (NZI) materials, i.e., materials having a phase refractive index close to zero, are known to enhance or inhibit light-matter interactions. Most theoretical derivations of fundamental radiative processes ...
    • Near-zero-index media as electromagnetic ideal fluids 

      Liberal Olleta, Íñigo Upna Orcid; Lobet, Michaël; Li, Yue; Engheta, Nader (National Academy of Sciences, 2020)   Artículo / Artikulua  OpenAccess
      Near-zero-index (NZI) supercoupling, the transmission of electromagnetic waves inside a waveguide irrespective of its shape, is a counterintuitive wave effect that finds applications in optical interconnects and engineering ...
    • Nonlinear metamaterial absorbers enabled by photonic doping of epsilon-near-zero metastructures 

      Nahvi, Ehsan; Liberal Olleta, Íñigo Upna Orcid; Engheta, Nader (American Physical Society, 2020)   Artículo / Artikulua  OpenAccess
      We theoretically demonstrate an approach for designing absorbers with strongly intensity-dependent absorption. The proposed absorbers consist of a spacer layer between a top resistive sheet and an underlying metallic ...
    • On the performance of an ENZ-based sensor using transmission line theory and effective medium approach 

      Pacheco-Peña, Víctor Upna Orcid; Beruete Díaz, Miguel Upna Orcid; Rodríguez Ulibarri, Pablo Upna Orcid; Engheta, Nader (IOP Publishing, 2019)   Artículo / Artikulua  OpenAccess
      In this paper we perform an in-depth theoretical studyofa sensing platform based on epsilon-near- zero (ENZ) metamaterials. The structure proposed for sensing is a narrow metallic waveguide channel. An equivalent circuit ...
    • Soft surfaces and enhanced nonlinearity enabled via epsilon-near-zero media doped with zero-area perfect electric conductor inclusions 

      Nahvi, Ehsan; Liberal Olleta, Íñigo Upna Orcid; Engheta, Nader (Optical Society of America, 2020)   Artículo / Artikulua  OpenAccess
      Introducing a dielectric inclusion inside an epsilon-near-zero (ENZ) host has been shown to dramatically affect the effective permeability of the host for a TM-polarized incident wave, a concept coined as photonic doping ...
    • Structural dispersion-based reduction of loss in epsilon-near-zero and surface plasmon polariton waves 

      Li, Yue; Liberal Olleta, Íñigo Upna Orcid; Engheta, Nader (American Association for the Advancement of Science, 2019)   Artículo / Artikulua  OpenAccess
      The field of plasmonics has substantially affected the study of light-matter interactions at the subwavelength scale. However, dissipation losses still remain an inevitable obstacle in the development of plasmonic-based ...
    • Substrate-integrated photonic doping for near-zero-index devices 

      Zhou, Ziheng; Li, Yue; Li, Hao; Sun, Wangyu; Liberal Olleta, Íñigo Upna Orcid; Engheta, Nader (Nature Research, 2019)   Artículo / Artikulua  OpenAccess
      Near-zero-index (NZI) media, a medium with near zero permittivity and/or permeability, exhibits unique wave phenomena and exciting potential for multiple applications. However, previous proof-of-concept realizations of NZI ...
    • Terahertz epsilon-near-zero graded-index lens 

      Torres Landívar, Víctor Upna; Pacheco-Peña, Víctor Upna Orcid; Rodríguez Ulibarri, Pablo Upna Orcid; Navarro Cía, Miguel Upna Orcid; Beruete Díaz, Miguel Upna Orcid; Sorolla Ayza, Mario Upna; Engheta, Nader (Optical Society of America, 2013)   Artículo / Artikulua  OpenAccess
      An epsilon-near-zero graded-index converging lens with planar faces is proposed and analyzed. Each perfectly-electric conducting (PEC) waveguide comprising the lens operates slightly above its cut-off frequency and has ...

      El Repositorio ha recibido la ayuda de la Fundación Española para la Ciencia y la Tecnología para la realización de actividades en el ámbito del fomento de la investigación científica de excelencia, en la Línea 2. Repositorios institucionales (convocatoria 2020-2021).
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