Scanning localized magnetic fields in a microfluidic device with a single nitrogen vacancy center

Area of Science:

• Quantum sensing
• Nanotechnology
• Microfluidics

Background:

• Nitrogen vacancy (NV) color centers in diamond offer high-sensitivity magnetic field sensing via optical detection of electron spin resonance (ESR).
• Integrating NV centers with microfluidic systems opens avenues for advanced chemical and biological sensing applications.

Purpose of the Study:

• To demonstrate a method for localized magnetometry within a microfluidic device.
• To achieve high spatial precision in mapping magnetic field distributions.

Main Methods:

• Utilizing a microfluidic device capable of three-dimensional manipulation of individual magnetic particles via flow control and magnetic actuation.
• Positioning magnetic particles near a single NV center in diamond.
• Optically detecting the induced Zeeman shift to measure the local magnetic field.

Main Results:

• Achieved a spatial precision of 48 nm for localized magnetometry.
• Demonstrated a magnetic field sensitivity of 17.5 μT Hz(-1/2).
• Successfully mapped the local magnetic field distribution of an individual magnetic particle.

Conclusions:

• The developed method enables accurate nanoscale mapping of magnetic field distributions.
• This technique is applicable to a wide range of target objects within microfluidic devices.
• The integration of NV centers and microfluidics provides a powerful tool for nanoscale magnetic field analysis.