Bound states in the continuum (BICs) are widely studied for their ability to confine light, produce sharp resonances for sensing applications and serve as avenues for lasing action with topological characteristics. Primarily, the formation of BICs in periodic photonic band gap structures are driven by symmetry incompatibility; structural manipulation or variation of incidence angle from incoming light. In this work, we report two modalities for driving the formation of BICs in terahertz metasurfaces. At normal incidence, we experimentally confirm polarization driven symmetry-protected BICs by the variation of the linear polarization state of light. In addition, we demonstrate through strong coupling of two radiative modes the formation of capacitively-driven Freidrich-Wintgen BICs, exotic modes which occur in off-Γ points not accessible by symmetry-protected BICs. The capacitance-mediated strong coupling at 0° polarization is verified to have a normalized coupling strength ratio of 4.17% obtained by the Jaynes-Cummings model. Furthermore, when the polarization angle is varied from 0° to 90° (0° ≤ ϕ < 90°), the Freidrich-Wintgen BIC is modulated until it is completely switched off at 90°.

This paper evaluates the potential for the real-time utilization of high frame rate image sequences using a fully parallel readout system. Multiple readout architectures for high frame rate imaging are compared. The application domain for a fully parallel readout system is identified, and the design for a fully parallel, monolithically integrated smart CMOS focal plane array is presented. This focal plane image processing chip, with an 8 2 8 array of Si CMOS detectors each of which have a dedicated on-chip current input first-order sigma-delta analogto-digital converter front end, has been fabricated, and test results for uniformity and linearity are presented.

We demonstrate an integrated evanescent-field multimode Mach-Zehnder interferometric chemical-biological sensor, fabricated on silicon, with sensitivity of parts per 10 9 achieved by modal pattern tracking and analysis. This sensor is fully compatible with the fabrication constraints of the silicon-complementary-metal-oxidesemiconductor (Si-CMOS) process. Furthermore, using the separately measured ellipsometric response together with the mass uptake of agent by the polymer sensing layer, we validate sensor performance via simulation and measure an absolute index sensitivity of 2.5ϫ 10 −6. We then extend this to a fully integrated chemical-biological sensor by considering the fundamental noise performance of CMOS detectors. We find that relatively short, Ͻ5000 m long, interferometric sensing elements, with modal pattern analysis, allow fully integrated optical sensors on Si-CMOS (assuming a 2.8 m pixel pitch) with an index sensitivity of ϳ9.2 ϫ 10 −7 and a corresponding concentration sensitivity of ϳ170 parts per 10 9 for methanol in N 2 .

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