Ultrathin Semiconductor Superabsorbers from the Visible to the Near-Infrared

Pau Molet, Juan Luis Garcia-Pomar, Cristiano Matricardi, Miquel Garriga, Maria Isabel Alonso, Agustín Mihi

    Research output: Contribution to journalArticleResearchpeer-review

    24 Citations (Scopus)


    © 2018 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim The design of ultrathin semiconducting materials that achieve broadband absorption is a long-sought-after goal of crucial importance for optoelectronic applications. To date, attempts to tackle this problem consisted either of the use of strong—but narrowband—or broader—but moderate—light-trapping mechanisms. Here, a strategy that achieves broadband optimal absorption in arbitrarily thin semiconductor materials for all energies above their bandgap is presented. This stems from the strong interplay between Brewster modes, sustained by judiciously nanostructured thin semiconductors on metal films, and photonic crystal modes. Broadband near-unity absorption in Ge ultrathin films is demonstrated, which extends from the visible to the Ge bandgap in the near-infrared and is robust against angle of incidence variation. The strategy follows an easy and scalable fabrication route enabled by soft nanoimprinting lithography, a technique that allows seamless integration in many optoelectronic fabrication procedures.
    Original languageEnglish
    Article number1705876
    JournalAdvanced Materials
    Issue number9
    Publication statusPublished - 1 Mar 2018


    • broadband absorption
    • nanostructuring
    • photonic crystal
    • soft lithography


    Dive into the research topics of 'Ultrathin Semiconductor Superabsorbers from the Visible to the Near-Infrared'. Together they form a unique fingerprint.

    Cite this