Photonic sensors based upon high‐quality microcavities have found a wide variety of applications ranging from inertial sensing, electro‐ and magnetometry to chemical and biological sensing. These sensors have a dynamic range limited by the linewidth of the cavity mode transducing the input. This dynamic range not only determines the range of the signal strength that can be detected, but also affects the resilience of the sensor against large deteriorating external perturbations and shocks in a practical environment. Unfortunately, there is a general trade‐off between the detection sensitivity and the dynamic range, which undermines the performance of all microcavity‐based sensors. Here, an approach is proposed to extend the dynamic range significantly beyond the cavity linewidth limit by exploiting the periodic nature of the modulation signal, making measurements in the nonlinear transduction regime without degrading the detection sensitivity for weak signals. With a cavity optomechanical system, a dynamic range of over six times larger than the cavity linewidth is experimentally demonstrated, far beyond the conventional linear region of operation for such a sensor. This approach will help design microcavity‐based sensors to achieve high detection sensitivity and a large dynamic range at the same time, a crucial property for their use in a practical environment.
- Award ID(s):
- 2110591
- NSF-PAR ID:
- 10346213
- Date Published:
- Journal Name:
- Photonics
- Volume:
- 9
- Issue:
- 2
- ISSN:
- 2304-6732
- Page Range / eLocation ID:
- 61
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/photonics9020061
