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In this paper, we study both theoretically and experimentally the sensitivity of bimodal interferometric sensors where interference occurs between two plasmonic modes with different properties propagating in the same physical waveguide. In contrast to the well-known Mach–Zehnder interferometric (MZI) sensor, we show for the first time that the sensitivity of the bimodal sensor is independent of the sensing area length. This is validated by applying the theory to an integrated plasmo-photonic bimodal sensor that comprises an aluminum (Al) plasmonic stripe waveguide co-integrated between two accessible SU-8 photonic waveguides. A series of such bimodal sensors utilizing plasmonic stripes of different lengths were numerically simulated, demonstrating bulk refractive index (RI) sensitivities around 5700 nm/RIU for all sensor variants, confirming the theoretical results. The theoretical and numerical results were also validated experimentally through chip-level RI sensing experiments on three fabricated SU-8/Al bimodal sensors with plasmonic sensing lengths of 50, 75, and 100 μm. The obtained experimental RI sensitivities were found to be very close and equal to 4464, 4386, and 4362 nm/RIU, respectively, confirming that the sensing length has no effect on the bimodal sensor sensitivity. The above outcome alleviates the design and optical loss constraints, paving the way for more compact and powerful sensors that can achieve high sensitivity values at ultra-short sensing lengths. [ABSTRACT FROM AUTHOR]

2D materials display very promising intrinsic material properties, with multiple applications in electronics, photonics, and sensing. In particular layered platinum diselenide has shown high potential due to its layer‐dependent tunable bandgap, low‐temperature growth, and high environmental stability. Here, the conformal and area selective (AS) low‐temperature growth of layered PtSe2 is presented defining a new paradigm for 2D material integration. The thermally‐assisted conversion of platinum which is deposited by AS atomic layer deposition to PtSe2 is demonstrated on various substrates with a distinct 3D topography. Further the viability of the approach is presented by successful on‐chip integration of hybrid semiconductor devices, namely by the manufacture of a highly sensitive ammonia sensors channel with 3D topography and fully integrated infrared‐photodetectors on silicon photonics waveguides. The presented methodologies of conformal and AS growth therefore lay the foundation for new design routes for the synthesis of more complex hybrid structures with 2D materials. [ABSTRACT FROM AUTHOR]

The vertical charge transport through Si/SiOx multiple quantum wells (QWs) is investigated. Upon thermal annealing, segregation of excess Si from the SiOx layers leads to the formation of highly conductive pathways between Si grains from adjacent QWs separated by ultrathin silicon oxide barriers with barrier heights of 0.53–0.65 eV. Compared to stoichiometric Si/SiO2 layer stacks, conductivity is increased by up to ten orders of magnitude, which opens the way to an efficient charge carrier extraction in photovoltaic systems with distinct quantum confinement. [ABSTRACT FROM AUTHOR]

We present a technology platform supported by a new process design kit (PDK) that integrates two types of aluminum plasmonic waveguides with Si $_{3}$ N $_{4}$ photonics towards CMOS-compatible plasmo-photonic integrated circuits for sensing applications. More specifically, we demonstrate the fabrication of aluminum slot waveguide via e-beam lithography (EBL) on top of the Si $_{3}$ N $_{4}$ waveguide and an optimized fabrication process of aluminum plasmonic stripe waveguides within a CMOS foundry using EBL. Experimental measurements revealed a propagation length of 6.2 μm for the plasmonic slot waveguide in water at 1550 nm, reporting the first ever experimental demonstration of a plasmonic slot waveguide based on CMOS compatible metal materials in liquid environment. Propagation length in water for the aluminum stripe was measured equal to 66.8 μm which is, to the best of our knowledge, the highest value among all single-mode Al-based plasmonic waveguides presented so far at 1550 nm. Moreover, we evince with simulation data the sensing capabilities of the proposed structures when incorporated in a Si $_{3}$ N $_{4}$ -based interferometric configuration, yielding bulk sensitivity values up to 80 nm/RIU and 1300 nm/RIU, corresponding to an accumulated phase change per unit length of 0.77 π/RIU/μm and 1.26 π/RIU/μm for the aluminum slot and aluminum stripe waveguide, respectively. [ABSTRACT FROM AUTHOR]

Here in this work, we study the electro-refractive modulation of CVD grown single layer graphene placed on top of a silicon microring resonator biased using a polymer electrolyte gate. A voltage length product for a phase shift of π, VπL = 2.7 Vmm has been extracted, which is better compared to silicon depletion horizontal and interleaved pn junction type phase modulators and competitive with Silicon-Insulator-Silicon Capacitor modulators. [ABSTRACT FROM PUBLISHER]

ABSTRACT An algorithm to calculate the current in the two-diode equivalent circuit of a solar cell is described and characterized in detail. It enables fitting measured current-voltage characteristics with hundreds of voltage points and six fit parameters at practically instantaneous speeds and can handle thousands of voltage points within a few seconds, without simplifications of the two-diode model. This performance enables routine two-diode model parameter extraction at in-line speeds, which may help to enhance cell characterization for module integration. The source code is publicly available. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT In this paper, we demonstrate single-sided screen-printed emitters in thin monocrystalline Czochralski silicon (Cz-Si) wafers with an improved gettering of iron compared with conventional double-sided POCl3 emitters. The phosphorus dopant pastes used have to be chosen carefully to provide a sufficiently low emitter sheet resistance and to avoid iron contamination. The iron concentration is determined in a non-destructive way from the minority carrier lifetime obtained by quasi-steady-state photoconductance measurements, down to levels not yet demonstrated for screen-printed emitters. In addition, the well-known metastable boron-oxygen complexes in Cz-Si have been transferred into a stable state by light-induced degradation prior to these measurements. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]