Publications by authors named "Carl A Villarruel"

This paper reports the demonstration of a widely-translatable fiber-optic mirror based on the motion of liquid metal through the hollow core of a photonic bandgap fiber. By moving a liquid metal mirror within the hollow core of an optical fiber, large, continuous changes in optical path length are achieved in a comparatively small package. A fiber-optic device is demonstrated which provided a continuously-variable optical path length of over 3.

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This paper reports the demonstration of a continuously-tunable true-time delay line for microwave photonics and optical communications capable of high-resolution phase control throughout the 1-100 GHz modulation range. A fiber-coupled device is demonstrated with 75 ps of continuous delay tuning range, 3 dB optical insertion loss, and minimal RF amplitude and phase variation over the 4-18 GHz band. Measured delay ripple was less than 0.

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This paper presents a detailed investigation of the physical mechanisms underlying the disruption of a lithium niobate electrooptic modulator by RF pulses. It is shown that short-term modulator disruption is a direct consequence of resistive heating within the metal conductor of the coplanar waveguide electrode, which leads to a thermo-optic optical phase shift in the waveguides of the modulator. Resistive heating is also shown to contribute to permanent modulator damage at higher RF power.

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