We present a new method for the extraction of quantitative phase data from microscopic phase samples by use of partially coherent illumination and an ordinary transmission microscope. The technique produces quantitative images of the phase profile of the sample without phase unwrapping. The technique is able to recover phase even in the presence of amplitude modulation, making it significantly more powerful than existing methods of phase microscopy. We demonstrate the technique by providing quantitatively correct phase images of well-characterized test samples and show that the results obtained for more-complex samples correlate with structures observed with Nomarski differential interference contrast techniques.

Hot charge carrier extraction from metallic nanostructures is a very promising approach for applications in photocatalysis, photovoltaics, and photodetection. One limitation is that many metallic nanostructures support a single plasmon resonance thus restricting the light-to-charge-carrier activity to a spectral band. Here we demonstrate that a monolayer of plasmonic nanoparticles can be assembled on a multistack layered configuration to achieve broadband, near-unit light absorption, which is spatially localized on the nanoparticle layer. We show that this enhanced light absorbance leads to ∼40-fold increases in the photon-to-electron conversion efficiency by the plasmonic nanostructures. We developed a model that successfully captures the essential physics of the plasmonic hot electron charge generation and separation in these structures. This model also allowed us to establish that efficient hot carrier extraction is limited to spectral regions where (i) the photons have energies higher than the Schottky junctions and (ii) the absorption of light is localized on the metal nanoparticles.

Plasmonic dark modes are pure near-field modes that can arise from the plasmon hybridization in a set of interacting nanoparticles. When compared to bright modes, dark modes have longer lifetimes due to their lack of a net dipole moment, making them attractive for a number of applications. We demonstrate the excitation and optical detection of a collective dark plasmonic mode from individual plasmonic trimers. The trimers consist of triangular arrangements of gold nanorods, and due to this symmetry, the lowest-energy dark plasmonic mode can interact with radially polarized light. The experimental data presented confirm the excitation of this mode, and its assignment is supported with an electrostatic approximation wherein these dark modes are described in terms of plasmon hybridization. The strong confinement of energy in these modes and their associated near fields hold great promise for achieving strong coupling to single photon emitters.

We demonstrate a new plasmonic pixel (PP) design that produces a full-color optical response over macroscopic dimensions. The pixel design employs arrays of aluminum nanorods "floating" above their Babinet complementary screen, Concepts from conventional cyan magenta yellow key (CMYK) printing techniques and red green blue (RGB) digital displays are integrated with nanophotonic design principles and adapted to the production of PP elements. The fundamental PP color blocks of CMYK are implemented via a composite plasmonic nanoantenna/slot design and then mixed in a digital display analog 3 × 3 array to produce a broad-gamut PP. The PP goes beyond current investigations into plasmonic color production by enabling a broad color gamut and physically large plasmonic color features/devices/images. The use of nanorods also leads to a color response that is polarization tunable. Furthermore, devices are fabricated using aluminum and the fabrication strategy is compatible with inexpensive, rapid-throughput, nanoimprint approaches. Here we quantify, both computationally and experimentally, the performance of the PP. Spectral data from a test palette is obtained and a large area (>1.5 cm lateral dimensions) reproduction of a photograph is generated exemplifying the technqiue.

Background:The refractive index (RI) of cellular material provides fundamental biophysical information about the composition and organizational structure of cells. Efforts to describe the refractive properties of cells have been significantly impeded by the experimental difficulties encountered in measuring viable cell RI. In this report we describe a procedure for the application of quantitative phase microscopy in conjunction with confocal microscopy to measure the RI of a cultured muscle cell specimen. Methods: The experimental strategy involved calculation of cell thickness by using confocal optical sectioning procedures, construction of a phase map of the same cell using quantitative phase microscopy, and selection of cellular regions of interest to solve for the cell RI. Results: Mean cell thickness and phase values for six cell regions (five cytoplasmic and one nuclear) were deter-