Publications by authors named "DE Oates"

We present experimental evidence for the observation of the nonlinear Meissner effect in high-quality epitaxial yttrium barium copper oxide thin films by measuring their intermodulation distortion at microwave frequencies versus temperature. Most of the films measured show a characteristic increase in nonlinearity at low temperatures as predicted by the nonlinear Meissner effect. We could measure the nonlinear Meissner effect because intermodulation distortion measurements are an extremely sensitive method that can detect changes in the penetration depth of the order of 1 part in 10(5).

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The sensitivity of surface-acoustic-wave detection is extended by several orders of magnitude to a surface-specific absorbance of alphal ~ 10(-9) for a power density of 1 GW/cm(2) using a narrow-bandwidth interdigitated surface-acousticwave detector and an optical irradiation pattern to provide a matched acoustic signal. Major advantages include narrow-bandwidth detection and a large irradiated area that permits more optical energy on the sample. A rapid, nondestructive, reproducible liquid-bonding technique, which permits the extension of these measurements to a wide variety of samples, is demonstrated.

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Microwave bulk-acoustic-wave reflection-grating resonators.

IEEE Trans Ultrason Ferroelectr Freq Control

October 2012

A technique for fabrication of bulk-acoustic-wave (BAW) resonators operating at fundamental frequencies between 1 and 10 GHz is presented. The resonators utilize a reflection grating made by optical holographic methods in iron-doped lithium niobate. Q factors of 30000 at 1 GHz have been demonstrated.

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