Microscale 3D imaging by magnetic resonance force microscopy using full-volume Fourier- and Hadamard-encoding

Area of Science:

• Physics
• Materials Science
• Nanotechnology

Background:

• Magnetic Resonance Force Microscopy (MRFM) is a powerful technique for nanoscale magnetic imaging.
• Achieving high spatial resolution, particularly in three dimensions, remains a key challenge in MRFM.

Purpose of the Study:

• To describe a novel method for three-dimensional (3D) spatially resolved full-volume imaging using MRFM at room temperature.
• To demonstrate the capability of this technique for high-resolution imaging of material structures.

Main Methods:

• Utilized the magnetic-field gradient of a ferromagnetic particle for z-dimension spatial resolution and force detection.
• Employed gradients of radiofrequency pulses from microcoils for x- and y-dimension spatial resolution.
• Applied Hadamard- and Fourier-encoding schemes to enhance measurement sensitivity through multiplexing.

Main Results:

• Successfully reconstructed a 3D image of a patterned (NH4)2SO4 crystal sample.
• Achieved a voxel volume of approximately 5 μm³ (1.2 μm × 3.0 μm × 1.4 μm in x, y, and z dimensions).
• Demonstrated room-temperature, full-volume 3D imaging capability with high spatial resolution.

Conclusions:

• The developed MRFM technique enables high-resolution, three-dimensional imaging at room temperature.
• This advancement opens possibilities for detailed nanoscale characterization of various materials.
• The method effectively combines magnetic field gradients and RF pulse gradients for precise spatial localization.