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Multipoint Lock-in Detection for Diamond Nitrogen-Vacancy Magnetometry Using DDS-Based Frequency-Shift Keying
Qidi Hu1,2, Luheng Cheng1,2, Yushan Liu1
1Research Center for Quantum Sensing, Zhejiang Lab, Hangzhou 311000, China.
Micromachines
|January 26, 2024
Summary
Researchers developed a new method for multipoint lock-in detection using a single device, enabling advanced sensing with nitrogen-vacancy (NV) centers in diamonds. This technique simplifies complex measurements for quantum applications.
Area of Science:
- Quantum Sensing
- Materials Science
- Nanotechnology
Background:
- Nitrogen-vacancy (NV) centers in diamonds are advanced multiphysics sensors.
- Lock-in amplifiers (LIAs) are crucial for monitoring photoluminescence changes in NV centers.
- Current methods face complexity when using multiple resonant points for vector or joint sensing.
Purpose of the Study:
- To present a novel scheme for multipoint lock-in detection using a single-channel device.
- To overcome the complexity of multi-resonant point sensing in NV-based applications.
- To enable efficient and versatile quantum sensing.
Main Methods:
- Utilized a direct digital synthesizer (DDS) for frequency control.
- Implemented frequency-shift keying (FSK) technique for encoding resonant points.
- Achieved a maximum bandwidth of 1.4 GHz for flexible frequency hopping.
Main Results:
- Demonstrated successful multipoint lock-in detection with a single-channel device.
- Enabled encoding of an unlimited number of resonant points.
- Validated the method through experimental implementation.
Conclusions:
- The novel DDS and FSK-based scheme simplifies multipoint lock-in detection for NV centers.
- This method is highly applicable to quantum multi-frequency excitation applications.
- The technique is particularly beneficial for portable and highly mobile sensing systems.
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