Nanowires for Biosensing: Lightguiding of Fluorescence as a Function of Diameter and Wavelength

Damiano Verardo, Frida Lindberg, Nicklas Anttu, Cassandra Niman, Mercy Lard, Aleksandra Dabkowska, Tommy Nylander, Alf Månsson, Christelle Prinz, Heiner Linke

Research output: Contribution to journalArticlepeer-review

24 Citations (SciVal)

Abstract

Semiconductor nanowires can act as nanoscaled optical fibers, enabling them to guide and concentrate light emitted by surface-bound fluorophores, potentially enhancing the sensitivity of optical biosensing. While parameters such as the nanowire geometry and the fluorophore wavelength can be expected to strongly influence this lightguiding effect, no detailed description of their effect on in-coupling of fluorescent emission is available to date. Here, we use confocal imaging to quantify the lightguiding effect in GaP nanowires as a function of nanowire geometry and light wavelength. Using a combination of finite-difference time-domain simulations and analytical approaches, we identify the role of multiple waveguide modes for the observed lightguiding. The normalized frequency parameter, based on the step-index approximation, predicts the lightguiding ability of the nanowires as a function of diameter and fluorophore wavelength, providing a useful guide for the design of optical biosensors based on nanowires.
Original languageEnglish
Pages (from-to)4796–4802
JournalNano Letters
Volume18
Issue number8
DOIs
Publication statusPublished - 2018 Jul 12

Subject classification (UKÄ)

  • Other Physics Topics

Fingerprint

Dive into the research topics of 'Nanowires for Biosensing: Lightguiding of Fluorescence as a Function of Diameter and Wavelength'. Together they form a unique fingerprint.

Cite this