title: Cloaking of solar cell contacts at the onset of Rayleigh scattering.
abstract: Electrical contacts on the top surface of solar cells and light emitting diodes cause shadow losses. The phenomenon of extraordinary optical transmission through arrays of subwavelength holes suggests the possibility of engineering such contacts to reduce the shadow using plasmonics, but resonance effects occur only at specific wavelengths. Here we describe instead a broadband effect of enhanced light transmission through arrays of subwavelength metallic wires, due to the fact that, in the absence of resonances, metal wires asymptotically tend to invisibility in the small size limit regardless of the fraction of the device area taken up by the contacts. The effect occurs for wires more than an order of magnitude thicker than the transparency limit for metal thin films. Finite difference in time domain calculations predict that it is possible to have high cloaking efficiencies in a broadband wavelength range, and we experimentally demonstrate contact shadow losses less than half of the geometric shadow.
authors.affiliation: IMM-Instituto de Microelectrónica de Madrid (CNM-CSIC), Isaac Newton 8, PTM, E-28760 Tres Cantos, Madrid, Spain.
authors.forename: Etor
authors.initials: E
authors.lastname: San Román
authors.affiliation: IMM-Instituto de Microelectrónica de Madrid (CNM-CSIC), Isaac Newton 8, PTM, E-28760 Tres Cantos, Madrid, Spain.
authors.forename: Alan
authors.initials: A
authors.lastname: Vitrey
authors.affiliation: IMM-Instituto de Microelectrónica de Madrid (CNM-CSIC), Isaac Newton 8, PTM, E-28760 Tres Cantos, Madrid, Spain.
authors.forename: Jerónimo
authors.initials: J
authors.lastname: Buencuerpo
authors.affiliation: IMM-Instituto de Microelectrónica de Madrid (CNM-CSIC), Isaac Newton 8, PTM, E-28760 Tres Cantos, Madrid, Spain.
authors.forename: Iván
authors.initials: I
authors.lastname: Prieto
authors.affiliation: IMM-Instituto de Microelectrónica de Madrid (CNM-CSIC), Isaac Newton 8, PTM, E-28760 Tres Cantos, Madrid, Spain.
authors.forename: José M
authors.initials: JM
authors.lastname: Llorens
authors.affiliation: IMM-Instituto de Microelectrónica de Madrid (CNM-CSIC), Isaac Newton 8, PTM, E-28760 Tres Cantos, Madrid, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: García-Martín
authors.affiliation: IMM-Instituto de Microelectrónica de Madrid (CNM-CSIC), Isaac Newton 8, PTM, E-28760 Tres Cantos, Madrid, Spain.
authors.forename: Benito
authors.initials: B
authors.lastname: Alén
authors.affiliation: Center for High Technology Materials, University of New Mexico, Albuquerque, NM 87106, USA.
authors.forename: Anabil
authors.initials: A
authors.lastname: Chaudhuri
authors.affiliation: Center for High Technology Materials, University of New Mexico, Albuquerque, NM 87106, USA.
authors.forename: Alexander
authors.initials: A
authors.lastname: Neumann
authors.affiliation: Center for High Technology Materials, University of New Mexico, Albuquerque, NM 87106, USA.
authors.forename: S R J
authors.initials: SR
authors.lastname: Brueck
authors.affiliation: IMM-Instituto de Microelectrónica de Madrid (CNM-CSIC), Isaac Newton 8, PTM, E-28760 Tres Cantos, Madrid, Spain.
authors.forename: José M
authors.initials: JM
authors.lastname: Ripalda