title: Imaging through plasmonic nanoparticles.
abstract: The optical properties of metallic nanoparticles with plasmon resonances have been studied extensively, typically by measuring the transmission of light, as a function of wavelength, through a nanoparticle suspension. One question that has not yet been addressed, however, is how an image is transmitted through such a suspension of absorber-scatterers, in other words, how the various spatial frequencies are attenuated as they pass through the nanoparticle host medium. Here, we examine how the optical properties of a suspension of plasmonic nanoparticles affect the transmitted image. We use two distinct ways to assess transmitted image quality: the structural similarity index (SSIM), a perceptual distortion metric based on the human visual system, and the modulation transfer function (MTF), which assesses the resolvable spatial frequencies. We show that perceived image quality, as well as spatial resolution, are both dependent on the scattering and absorption cross-sections of the constituent nanoparticles. Surprisingly, we observe a nonlinear dependence of image quality on optical density by varying optical path length and nanoparticle concentration. This work is a first step toward understanding the requirements for visualizing and resolving objects through media consisting of subwavelength absorber-scatterer structures, an approach that should also prove useful in the assessment of metamaterial or metasurface-based optical imaging systems.
authors.affiliation: Department of Electrical and Computer Engineering, Rice University, Houston, TX 77005;
authors.forename: Mehbuba
authors.initials: M
authors.lastname: Tanzid
authors.affiliation: Department of Electrical and Computer Engineering, Rice University, Houston, TX 77005;
authors.forename: Ali
authors.initials: A
authors.lastname: Sobhani
authors.affiliation: Department of Chemistry, Rice University, Houston, TX 77005;
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: DeSantis
authors.affiliation: Department of Chemistry, Rice University, Houston, TX 77005;
authors.forename: Yao
authors.initials: Y
authors.lastname: Cui
authors.affiliation: Department of Physics and Astronomy, Rice University, Houston, TX 77005.
authors.forename: Nathaniel J
authors.initials: NJ
authors.lastname: Hogan
authors.affiliation: Department of Electrical and Computer Engineering, Rice University, Houston, TX 77005;
authors.forename: Adam
authors.initials: A
authors.lastname: Samaniego
authors.affiliation: Department of Electrical and Computer Engineering, Rice University, Houston, TX 77005;
authors.forename: Ashok
authors.initials: A
authors.lastname: Veeraraghavan
authors.affiliation: Department of Electrical and Computer Engineering, Rice University, Houston, TX 77005; Department of Chemistry, Rice University, Houston, TX 77005; Department of Physics and Astronomy, Rice University, Houston, TX 77005 halas@rice.edu.
authors.forename: Naomi J
authors.initials: NJ
authors.lastname: Halas
keywords: imaging; light scattering; metamaterials; nanoparticles; plasmonics