• Photonics Research
  • Vol. 9, Issue 10, 10001984 (2021)
Dengwei Zhang1、4, Zhihang Zhang1, Heming Wei2、3、*, Jianrong Qiu1, and Sridhar Krishnaswamy3
Author Affiliations
  • 1State Key Laboratory of Modern Optical Instrumentation, Zhejiang University, Hangzhou 310027, China
  • 2Key Laboratory of Specialty Fiber Optics and Optical Access Networks, Joint International Research Laboratory of Specialty Fiber Optics and Advanced Communication, Shanghai University, Shanghai 200444, China
  • 3Center for Smart Structures & Materials, Department of Mechanical Engineering, Northwestern University, Evanston, Illinois 60208, USA
  • 4e-mail: seaskyzdw@zju.edu.cn
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    A high-birefringence spiral Sagnac waveguide (SSW) device fabricated via direct laser writing (DLW) using a two-photon polymerization (2PP) technique is proposed, designed, and experimentally demonstrated as an ultrahigh magnetic field sensor. The sensor comprises a Y-style tapered waveguide and an SSW containing two microfluidic channels. The SSW has a total length of 2.4 mm and a spiral radius of 200 μm. Due to the asymmetric structure, the SSW has a high birefringence of 0.016, which can be designed as a magnetic field sensor, as a magnetic fluid can be filled into the microfluidic channel changing the guiding mode and the birefringence and consequently leading to a change in phase of the interferometer when the applied magnetic field changes. The experimental results show that the proposed photonic device has a sensitivity to magnetic fields as high as 0.48 nm/Oe within a range from 10 to 100 Oe. The proposed device is very stable and easy to fabricate, and it can therefore be used for weak magnetic field detection.
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    Dengwei Zhang, Zhihang Zhang, Heming Wei, Jianrong Qiu, Sridhar Krishnaswamy. Direct laser writing spiral Sagnac waveguide for ultrahigh magnetic field sensing[J]. Photonics Research, 2021, 9(10): 10001984
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    Category: Optical Devices
    Received: Jun. 10, 2021
    Accepted: Jul. 29, 2021
    Published Online: Sep. 15, 2021
    The Author Email: Heming Wei (wei.optics@gmail.com)