Publications by authors named "George A Brawley"
Article Synopsis
- * This research demonstrates a method to break the symmetry between position and momentum, allowing for the preparation of a thermally squeezed mechanical state through fast continuous measurements.
- * The findings suggest that using collective measurements on multiple mechanical modes can enhance measurement speed and state preparation, potentially enabling room temperature quantum squeezing with current technology.
We revisit quantum state preparation of an oscillator by continuous linear position measurement. Quite general analytical expressions are derived for the conditioned state of the oscillator. Remarkably, we predict that quantum squeezing is possible outside of both the backaction dominated and quantum coherent oscillation regimes, relaxing experimental requirements even compared to ground-state cooling.
View Article and Find Full Text PDFA cavity optomechanical magneto-meter operating in the 100 pT range is reported. The device operates at earth field, achieves tens of megahertz bandwidth with 60 μm spatial resolution and microwatt optical-power requirements. These unique capabilities may have a broad range of applications including cryogen-free and microfluidic magnetic resonance imaging (MRI), and investigation of spin-physics in condensed matter systems.
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- Whispering gallery mode biosensors can detect single proteins without labeling and allow real-time observation of motor molecules, but are limited by low frequency laser noise.
- A new technique for these biosensors uses direct detection of back-scattered light, which is immune to frequency noise and reduces thermorefractive noise.
- This method achieves a significant 27 dB noise suppression, improving frequency shift sensitivity to 76 kHz and paving the way for advanced single molecule studies and highly sensitive biosensors.
We investigate the dynamics of photoinduced index changes in chalcogenide As(2)S(3) fibers. Using a novel phase sensitive technique for measuring the photoinduced index change, we find that the index evolution is a two-stage process: it consists of a fast reduction and a subsequent slow increase in the refractive index. We show that the index change depends strongly on the beam intensity with both positive and negative changes possible.
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