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Brillouin microscopy has recently emerged as a powerful tool for mechanical property measurements in biomedical sensing and imaging applications. Impulsive stimulated Brillouin scattering (ISBS) microscopy has been proposed for faster and more accurate measurements, which do not rely on stable narrow-band lasers and thermally-drifting etalon-based spectrometers. However, the spectral resolution of ISBS-based signal has not been significantly explored. In this report, the ISBS spectral profile has been investigated as a function of the pump beam’s spatial geometry, and novel methodologies have been developed for accurate spectral assessment. The ISBS linewidth was found to consistently decrease with increasing pump-beam diameter. These findings provide the means for improved spectral resolution measurements and pave the way to broader applications of ISBS microscopy.
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Entanglement-Enhanced Interferometry in Optical Fiber
Fiber-based interferometry with entangled photons can provide sub-shot-noise resolution, which is ideal for photon-starved applications. Simulations demonstrate that measurements with realistic losses and other imperfections show quantum-enhanced phase resolution for practical applications.
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- Award ID(s):
- 1838435
- PAR ID:
- 10486801
- Publisher / Repository:
- Optica Publishing Group
- Date Published:
- Journal Name:
- Conference on Lasers and Electrooptics
- ISSN:
- 2160-9020
- ISBN:
- 978-1-943580-91-0
- Page Range / eLocation ID:
- FTh2O.7
- Format(s):
- Medium: X
- Location:
- San Jose, California
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1364/CLEO_QELS.2021.FTh2O.7
