Sensitivity improvement of a single-NV diamond magnetometer using a chiral waveguide

Area of Science:

• Quantum sensing
• Nanoscale physics
• Optics and photonics

Background:

• Single nitrogen-vacancy (NV) centers in diamond are used for nanoscale magnetic measurements.
• Current limitations include low contrast and poor photon collection efficiency, resulting in sensitivities around several nT/Hz.

Purpose of the Study:

• To design a highly sensitive diamond magnetometer.
• To overcome the sensitivity limitations of existing NV-center-based magnetometers.

Main Methods:

• Designing a diamond magnetometer incorporating a chiral waveguide.
• Numerical simulation to evaluate device performance.
• Assessing sensitivity against NV center position and orientation variations.

Main Results:

• Achieved a sensitivity of 170 pT/Hz, a significant improvement over existing methods.
• Demonstrated near-unity contrast and efficient photon collection.
• Confirmed robustness against NV center misalignment.

Conclusions:

• The proposed chiral waveguide approach dramatically enhances magnetometer sensitivity.
• This design enables highly sensitive nanoscale magnetic field detection.
• The robust performance suggests practical applications in various fields.