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Fong N.R.,Carleton University | Berini P.,University of Ottawa | Berini P.,Spectalis Corporation | Tait R.N.,Carleton University
Journal of Microelectromechanical Systems | Year: 2010

Mechanical bulge testing of thin free-standing CYTOP membranes for use with surface plasmon polariton (SPP) biosensors was conducted. Curve fitting of experimental data to a known deflection model allowed for the extraction of a Young's modulus of 1.3 ± 0.1 GPa and residual stress of 16.9 ± 1.3 MPa. The fracture stress for the membranes was observed to be 96.9 ± 8.4 MPa, which occurs at the membrane edges. © 2010 IEEE.

Scales C.,Center for Operational Research and Analysis | Berini P.,University of Ottawa | Berini P.,Spectalis Corporation
IEEE Journal of Quantum Electronics | Year: 2010

Phenomenological models for the internal quantum efficiency of Schottky barrier photodetectors suitable for the detection of optical radiation below the bandgap energy of the semiconductor are presented and discussed. The detection mechanism is internal photoemission from the metal film into the semiconductor substrate. Three detector configurations are considered: the first consists of a thick metal film on a semiconductor substrate forming a single Schottky barrier; the second consists of a thin metal film on a semiconductor substrate also forming a single Schottky barrier; and the third consists of a thin metal film buried in semiconductor and forming two Schottky barriers (one along each metal-semiconductor interface). In the three cases, illumination through the semiconductor substrate is assumed. The two thin-film configurations provide enhanced internal quantum efficiencies due to multiple hot carrier reflections within the metal film, with the double-barrier case providing the greatest enhancement due to emission over two barriers. The models proposed are based on assessing the emission probability of hot carriers as a function of their energy, taking into account multiple reflections within the metal film and energy losses due to internal scattering (e.g., with phonons and cold carriers). The thin-film single-barrier model was tested via comparisons with responsivity measurements reported in the literature for PtSi/p-Si and Pd2Si/p-Si detectors. © 2006 IEEE.

De Leon I.,University of Ottawa | Berini P.,University of Ottawa | Berini P.,Spectalis Corporation
Review of Scientific Instruments | Year: 2011

We describe techniques and an experimental setup to measure the gain and noise characteristics of a long-range surface plasmon-polariton amplifier consisting of a symmetric metallic stripe waveguide incorporating optically pumped dye molecules in the solution as the gain medium. The setup is capable of acquiring absolute power measurements at the amplifiers output over a narrow optical bandwidth. This allows independent characterization of the amplifiers gain via measurements of stimulated emission and via measurements of amplified spontaneous emission (ASE) over a narrow optical bandwidth, both obtained during the same experimental run. In addition, the absolute power measurements of ASE quantify directly the amplifiers noise. © 2011 American Institute of Physics.

Tencer M.,University of Ottawa | Nie H.-Y.,University of Western Ontario | Berini P.,University of Ottawa | Berini P.,Spectalis Corporation
Applied Surface Science | Year: 2011

A process of chemical differentiation of neighboring Au features on a substrate (for biosensing applications) involves a step, where after electrochemical removal of a self-assembled monolayer (SAM) from one feature, another SAM is deposited onto it by incubation with a different thiol. During this incubation step, other undesorbed features are also exposed to this thiol which may lead to a partial SAM-thiol exhange, the extent of which is a function of time. Here, such surface reactions were followed on polystalline Au in both directions using contact angle measurements and time-of-flight secondary ion mass spectrometry (ToF-SIMS). The thiols involved were dodecanethiol (DDT) which forms SAM promoting adsorption of proteins and 11-mercaptoundecyl)tri(ethylene glycol) (TPEG) whose SAM prevents such adsorption. The surface reactions in both directions cannot be described by a simple pseudo-first-order kinetics. It was found that while the DDT SAM interaction with a TPEG solution leads eventually to a total replacement, the reverse process, TPEG SAM interaction with DDT, leads to no noticeable exchange over the first 3 h and then asymptotically approaches ∼50% replacement. © 2010 Elsevier B.V.

De Leon I.,University of Ottawa | Berini P.,University of Ottawa | Berini P.,Spectalis Corporation
Nature Photonics | Year: 2010

Surface plasmon-polaritions, collective electron oscillations coupled to light waves at the surface of a metal, show unique properties that are valuable in a broad range of scientific fields. However, the intrinsic propagation loss of these waves poses a fundamental problem to many potential applications. To overcome this drawback, researchers have explored the possibility of loss compensation by means of surface plasmon-polarition amplification. Here we provide the first direct measurement of gain in propagating plasmons using the long-range surface plasmon-polariton supported by a symmetric metal stripe waveguide that incorporates optically pumped dye molecules in solution as the gain medium. The measured mode power gain is 8.55dBmm-1. Furthermore, it is shown that this new class of amplifier benefits from reduced spontaneous emission into the amplified mode, potentially leading to low-noise optical amplification. © 2010 Macmillan Publishers Limited. All rights reserved.

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