Browsing by Author "Dâna, A."
Now showing items 1-18 of 18
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Charge retention in quantized energy levels of nanocrystals
(Elsevier B.V., 2007)Understanding charging mechanisms and charge retention dynamics of nanocrystal (NC) memory devices is important in optimization of device design. Capacitance spectroscopy on PECVD grown germanium NCs embedded in a silicon ... -
Charging / discharging of thin PS / PMMA films as probed by dynamic x-ray photoelectron spectroscopy
(2007)Polystyrene / polymethyl methacrylate (PS-PMMA) thin films were analyzed for detecting phase separation as well as probing their electrical responses by XPS. It was also shown that electrical parameters like resistance or ... -
Chemically specific dynamic characterization of photovoltaic and photoconductivity effects of surface nanostructures
(American Chemical Society, 2010)We report characterization of photovoltaic and photoconductivity effects on nanostructured surfaces through light induced changes in the X-ray photoelectron spectra (XPS). The technique combines the chemical specificity ... -
Differentiation of domains in composite surface structures by charge-contrast x-ray photoelectron spectroscopy
(2007)An external bias is applied to two samples containing composite surface structures, while recording an XPS spectrum. Altering the polarity of the bias affects the extent of differential charging in domains that are chemically ... -
An elastomeric grating coupler
(IOP Institute of Physics, 2006)We report on a novel nondestructive and reversible method for coupling free space light to planar optical waveguides. In this method, an elastomeric grating is used to produce an effective refractive index modulation on ... -
Electrochemically tunable ultrafast optical response of graphene oxide
(A I P Publishing LLC, 2011)We demonstrate reversible and irreversible changes in the ultrafast optical response of multilayer graphene oxide thin films upon electrical and optical stimulus. The reversible effects are due to electrochemical modification ... -
Electrostatic force spectroscopy of near surface localized states
(Institute of Physics Publishing Ltd., 2005)Electrostatic force microscopy at cryogenic temperatures is used to probe the electrostatic interaction of a conductive atomic force microscopy tip and electronic charges trapped in localized states in an insulating layer ... -
Excitation of a surface plasmon with an elastomeric grating
(American Institute of Physics, 2005)We report on a new method to excite surface plasmon polaritons on a thin metal slab surface using an elastomeric grating which is fabricated by replica molding technique. The grating is placed on the metal surface which ... -
A figure of merit for optimization of nanocrystal flash memory design
(2008)Nanocrystals can be used as storage media for carriers in flash memories. The performance of a nanocrystal flash memory depends critically on the choice of nanocrystal size and density as well as on the choice of tunnel ... -
Grating coupler integrated photodiodes for plasmon resonance based sensing
(Royal Society of Chemistry, 2011)In this work, we demonstrate an integrated sensor combining a grating-coupled plasmon resonance surface with a planar photodiode. Plasmon enhanced transmission is employed as a sensitive refractive index (RI) sensing ... -
Lineshapes, shifts and broadenings in dynamical X-ray photoelectron spectroscopy
(2009)We describe in detail a model that can be used to estimate the X-ray photoelectron spectroscopic data of surfaces when a time varying bias or a modulation of the electrical properties of the surface is applied by external ... -
Parametrically coupled multiharmonic force imaging
(AIP Publishing, 2008)We report use of nonlinear tip-sample interactions to parametrically convert the frequency components of periodic tip-sample interaction forces to frequencies where they can be resonantly detected. One flexural mode of a ... -
Raman enhancement on a broadband meta-surface
(American Chemical Society, 2012-07-30)Plasmonic metamaterials allow confinement of light to deep subwavelength dimensions, while allowing for the tailoring of dispersion and electromagnetic mode density to enhance specific photonic properties. Optical resonances ... -
Reversible electrical reduction and oxidation of graphene oxide
(American Chemical Society, 2011)We demonstrate that graphene oxide can be reversibly reduced and oxidized using electrical stimulus. Controlled reduction and oxidation in two-terminal devices containing multilayer graphene oxide films are shown to result ... -
Two-dimensional x-ray photoelectron spectroscopy for composite surface analysis
(2008)We describe a method for obtaining two-dimensional X-ray photoelectron spectroscopic data derived from the frequency dependence of the XPS peaks recorded under electrical square-wave pulses, which control and affect the ... -
Utilizing embedded ultra-small Pt nanoparticles as charge trapping layer in flashristor memory cells
(Elsevier, 2018)In this study, a methodology for producing highly controlled and uniformly dispersed metal nanoparticles were developed by atomic layer deposition (ALD) technique. All-ALD grown thin film flash memory (TFFM) cells and their ... -
X-ray photoemission for probing charging/discharging dynamics
(American Chemical Society, 2006)A novel technique is introduced for probing charging/discharging dynamics of dielectric materials in which X-ray photoemission data is recorded while the sample rod is subjected to ± 10.0 V square-wave pulses with varying ... -
XPS measurements for probing dynamics of charging
(Elsevier, 2010)The technique of recording X-ray photoemission data while the sample rod is subjected to ±10.0 V (dc) or square-wave pulses (ac) with varying frequencies in the range of 10-3 to 103 Hz for probing charging/discharging ...
