Modern miniaturization and the digitalization of characterization instruments greatly facilitate the diffusion of technological advances in new fields and generate innovative applications. The concept of a portable, inexpensive and semi-automated biosensing platform, or lab-on-a-chip, is a vision shared by many researchers and venture industries. Under this scope, we present a semiconductor monolithic integration approach to conduct surface plasmon resonance studies. This technology is already commonly used for biochemical characterization in pharmaceutical industries, but we have reduced the technological platform to a few nanometers in scale on a semiconductor chip. We evaluate the signal quality of this nanophotonic device using hyperspectral-imaging technology, and we compare its performance with that of a standard prism-based commercial system. Two standard biochemical agents are employed for this characterization study: bovine serum albumin and inactivated influenza A virus. 2 However, the delocalization of arbitrary biochemical analyses is still a challenge today, where nanotechnogy could present solutions for the development of micro total analysis systems (mTAS) potentially capable of portable biodiagnostics. 3 We present here the results of an effort towards such a solution through a wholly integrated semiconductor-based surface plasmon resonance (SPR) nanometric platform.SPR is a well-established optical phenomenon where an electromagnetic (EM) beam of a specific energy and incident wavevector (angle) can induce a resonant group oscillation within the surface electrons of a metal-dielectric interface. 4 The resulting EM field is evanescent in nature, with typical confinement of 200 nm for visible light. Therefore, the coupling conditions of this resonance effect are very much dictated by the surface conditions within the evanescent field and can consequently be employed for many dynamic biochemistry studies. 5 The SPR biocharacterization platform presents many advantages over most other methods; its range of application is very broad, especially for unspecific binding studies, 5 the method can offer very high sensitivities to subtle surface refractive index changes 6 and even enable

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In this work we show that improved performances of terahertz emitters can be obtained using an ion implantation process. Our photoconductive materials consist of high-resistivity GaAs substrates. Terahertz pulses are generated by exciting our devices with ultrashort near-infrared laser pulses. The ion implantation introduces non-radiative centres, which reduce the carrier lifetime in GaAs. The presence of the charged defects also induces a redistribution of the electric field between the antenna electrodes. This effect has a huge influence on the amplitude of the radiated terahertz field. Results obtained as a function of the laser excitation power are discussed and a comparison of the performance of these devices with a conventional antenna-type emitter is given.