Robustness improvement of a nitrogen-vacancy magnetometer by a double driving method

Area of Science:

• Quantum sensing
• Solid-state spin physics
• Diamond-based magnetometry

Background:

• Nitrogen vacancy (NV) color centers in diamonds are sensitive electron spins for magnetic field measurements.
• Improving the robustness of NV quantum systems is crucial for advanced sensing and fundamental physics research.
• Existing NV magnetometers face challenges with thermal drift, impacting measurement accuracy.

Purpose of the Study:

• To enhance the robustness and sensitivity of NV magnetometers.
• To investigate and mitigate thermal drift issues in NV-based sensing.
• To introduce a novel method for improving continuous-wave NV magnetometer performance.

Main Methods:

• Implemented a double driving method to improve NV magnetometer robustness.
• Increased pumping power to enhance magnetometer sensitivity.
• Utilized infrared thermography to measure temperature drift in the diamond matrix.
• Developed a method to suppress resonance frequency drift caused by temperature changes.

Main Results:

• Achieved a 2.1-fold improvement in NV magnetometer sensitivity.
• Reduced magnetic noise density from 10 to 1.2 nT/Hz^1/2.
• Identified and quantified temperature drift of approximately 80 K in the diamond host under high power.
• Demonstrated suppression of resonance frequency drift using the double driving technique.

Conclusions:

• The double driving method effectively improves the robustness of continuous-wave NV magnetometers.
• Addressing temperature drift is critical for high-sensitivity magnetic field measurements with NV centers.
• This work provides a pathway for applying complex pulse protocols in advanced solid-state spin sensing applications.