D Bulla

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We present dynamically reconfigurable photonic crystal nanobeam cavities, operating at ~1550 nm, that can be continuously and reversibly tuned over a 9.5 nm wavelength range. The devices are formed by two coupled nanobeam cavities, and the tuning is achieved by varying the lateral gap between the nanobeams. An electrostatic force, obtained by applying bias(More)
We examine the cavity resonance tuning of high-Q silicon photonic crystal heterostructures by localized laser-assisted thermal oxidation using a 532 nm continuous wave laser focused to a 2.5 μm radius spot-size. The total shift is consistent with the parabolic rate law. A tuning range of up to 8.7 nm is achieved with ∼ 30 mW laser powers. Over this tuning(More)
We demonstrate up to 30 nm tuning of gallium phosphide photonic crystal cavities resonances at ~1.5 µm using a tapered optical fiber. The tuning is achieved through a combination of near-field perturbations and mechanical deformation of the membrane, both induced by the fiber probe. By exploiting this effect, we show fiber-coupled second harmonic generation(More)
An etch-free and cost-effective deposition and patterning method to fabricate mid-infrared chalcogenide glass waveguides for chemical sensing applications is introduced. As 2 S 3 raised strip optical waveguides are produced by casting a liquid solution of As 2 S 3 glass in capillary channel molds formed by soft lithography. Mid-IR transmission is(More)
The wavelength selective linear absorption in communication C-band is investigated in CMOS-processed PECVD silicon nitride rings. In the overcoupled region, the linear absorption loss lowers the on-resonance transmission of a ring resonator and increases its overall quality factor. Both the linear absorption and ring quality factor are maximized near 1520(More)
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